Energy Efficiency of Power Production: How Supercritical Carbon Dioxide Turbines Operate

Duane M. Tilden, P.Eng.                                    Sept 1, 2018

Foreword:

This is another article in an ongoing series of reports on the technological development of supercritical carbon dioxide in the power production and energy efficiency sectors of industry, power plants and utilities.

dodge-sco23 supercritical CO2 turbine

Figure 1. Size comparison of Supercritical Power Turbine to Conventional Steam Turbine (1)

Abstract:

The ever increasing search for improving energy and power production efficiency is a natural quest as developments in technology seek to be utilized to improve operations and supply cost effectively. The technologies behind the utilization of supercritical carbon dioxide and other such fluids have long been established. We are furthering our exploration into this sector of power production developing new technologies along the way to a smarter economy and modernization of infrastructure.

The Principle of Operation

Supercritical fluids can play an important role in developing better electricity generators because of their liquid- and gas-like properties. A supercritical fluid is an optimal working fluid because it has a temperature and pressure above its critical point, meaning that it doesn’t have a definite liquid or gas phase. Consequently, the slightest changes in pressure or temperature cause huge changes in the material’s density.

With any supercritical fluid, the ease of compressibility goes up, explains Stapp, so it becomes something more like water. Because supercritical CO2 also compresses more easily than steam, the amount of work done during the compression phase—normally accounting for 25 percent of the work performed inside the system—is dramatically reduced; the energy saved there greatly contributes to the turbine’s overall efficiency.

“We expand it like a gas, and pressurize it like a liquid,” says James Pasch, principle investigator of the Supercritical Carbon Dioxide Brayton Cycle Research and Development Program. “You can do this with any fluid, but supercritical carbon dioxide matches really well with ambient temperatures.”

Carbon dioxide is optimal for this application because it doesn’t go through a phase change at any point during the cycle. Its critical temperature, 88 degrees Fahrenheit, is very close to ambient temperature, which means the heat emitted by the turbine is the same temperature as the surrounding environment. Supercritical carbon dioxide is also very dense; at its critical point, the fluid is about half the density of water. So, in addition to being easier to compress, less work is required to cycle it back to the heat source for re-expansion.

The Brayton Cycle also offers direct environmental benefits. For one, it’s carbon neutral. The system takes carbon dioxide out of the air and puts it in the recompression cycle loop. Just as important is the fact that the system limits water usage by minimizing discharge, evaporation, and withdraw.

“That’s a big deal for the southwest,” says Gary Rochau, manager of Sandia’s Advanced Nuclear Concepts Department. Sandia’s generator can work in places where water is in limited supply. This puts it on par with the Palo Verde Nuclear Power Generating Station, a nuclear power plant in Arizona that uses recycled waste water as cooling water, saving groundwater and municipal water supplies for other uses. (2)

Figure 1. Illustration of a Supercritical CO2 Turbine [Peregrine Turbine Technologies] (2)

Advances in Materials and Technology

GE Reports first wrote about Hofer last year when he 3D printed a plastic prototype of the turbine. His team, partnered with Southwest Research Institute and Gas Technology Institute, has since submitted the design to the U.S. Department of Energy and won an $80 million award to build the 10 MW turbine. The turbine features a rotor that is 4.5 feet long, 7 inches in diameter, and only weighs 150 pounds. The engineers are now completing a scaled-down, 1 MW version of the machine and will test it in July at the Southwest Research Institute.

The idea of using CO2 to power a steam turbine has been around for a while. It first appeared in the late 1960s, and an MIT doctoral student resurrected it in 2004. “The industry has been really interested in the potential benefits of using CO2 in place of steam in advanced supercritical power plants,” Hofer says.

By “supercritical” Hofer means efficient power stations using CO2 squeezed and heated so much that it becomes a supercritical fluid, which behaves like a gas and a liquid at the same time. The world’s most efficient thermal power plant, RDK 8 in Germany, uses an “ultrasupercritical” steam turbine operating at 600 degrees Celsius and pressure of 4,000 pounds per square inch, more than what’s exerted when a bullet strikes a solid object.

Hofer says that the steam power plant technology “has been on a continuous march” to increase efficiency and steam temperature, but once it tops 700 degrees Celsius, “the CO2 cycle becomes more efficient than the steam cycle.” Hofer’s turbine and casing are made from a nickel-based superalloy because it can handle temperatures as high as 715 degrees Celsius and pressures approaching 3,600 pounds per square inch. “You need a high-strength material for a design like this,” he says.

 Figure 2. GE Global Research engineer Doug Hofer is building a compact and highly efficient turbine that fits on a conference table but can generate 10 megawatts (MW), enough to power 10,000 U.S. homes. The turbine, made from a nickel-based superalloy that can handle temperatures up to 715 degrees Celsius and pressures approaching 3,600 pounds per square inch, replaces steam with ultrahot and superpressurized carbon dioxide, allowing for a smaller design.

The hellish heat and pressure turn CO2 into a hot, dense liquid, allowing Hofer to shrink the turbine’s size and potentially increase its efficiency a few percentage points above where state-of-the-art steam systems operate today. “The pressure and fluid density at the exit of our turbine is two orders of magnitude higher than in a steam turbine,” Hofer says. “Therefore, to push the same mass through, you can have a much smaller turbine because the flow at the exit end is much denser.”

Hofer’s design uses a small amount of CO2 in a closed loop. “It’s important to remember that this is not a CO2 capture or sequestration technology,” he says. Hofer says that the technology, which is being developed as part of GE’s Ecomagination program, could one day start replacing steam turbines. “It’s on the multigenerational roadmap for steam-powered systems,” he says.

By virtue of becoming more efficient, the technology could help power-plant operators reduce greenhouse gas emissions. “The efficiency of converting coal into electricity matters: more efficient power plants use less fuel and emit less climate-damaging carbon dioxide,” wrote the authors of the International Energy Agency report on measuring coal plant performance. (3)

Previous Blog Posts on Supercritical Carbon Dioxide:

  1. https://duanetilden.com/2016/11/11/transitioning-oil-gas-wells-to-renewable-geothermal-energy/
  2. https://duanetilden.com/2016/03/13/supercritical-co2-used-for-solar-battery-power-system/
  3. https://duanetilden.com/2015/04/23/doe-invests-in-super-critical-carbon-dioxide-turbine-research-to-replace-steam-for-electric-power-generators/
  4. https://duanetilden.com/2013/10/29/supercritical-co2-refines-cogeneration-for-industry/
  5. https://duanetilden.com/2013/10/29/supercritical-co2-turbine-for-power-production-waste-heat-energy-recovery/
  6. https://duanetilden.com/2013/10/29/waste-heat-recovery-using-supercritical-co2-turbines-to-create-electrical-power/

 

References:

  1. supercritical-carbon-dioxide-power-cycles-starting-to-hit-the-market/
  2. supercritical-carbon-dioxide-can-make-electric-turbines-greener
  3. ecomagination-ge-building-co2-powered-turbine-generates-10-megawatts-fits-table/
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Microgrids and the Blockchain – Transforming the Energy Supply

Author: Duane M. Tilden, P.Eng.           Date: June 10, 2018

In the transition from the centralized utility is the development of the Micro-grid.  The Micro-grid offers many benefits to society, including; (a) use of renewable energy sources that reduce or eliminate the production of GHG’s, (b) increases in energy efficiency of energy transmission due to shortening of transmission distances and infrastructure, (c) improved municipal resilience against disaster and power reductions, and finally, (d) promotion of economic activity that improves universal standard of living. (1)

The Brooklyn Microgrid Experiment

A Network of Energy Cells (2)

In order to be successful, blockchain platforms and microgrids require a regulatory framework. In New York State, such a framework is provided by “Reforming the Energy Vision” (REV). The platform’s objectives are to minimize the vulnerability of the power supply system that became visible during Hurricane Sandy, to use more sources of renewable energy, and to reduce costs.

The Brooklyn Microgrid is a good test case for these objectives. “A microgrid is a nucleus that sets the stage for an energy future consisting of networks of energy cells,” says Stefan Jessenberger from Siemens’ Energy Management Division. “Blockchain also supports this process, because it makes it much easier to conduct energy trading within cells.”

Siemens Digital Grid, next47, and LO3 Energy all believe in the potential of blockchain-based microgrids, because this technology can be used wherever there are decentralized energy sources. “Our experiences with the Brooklyn Microgrid will certainly flow into future projects,” says Kessler.

 
Image #1: A Canal in Brooklyn, New York (5)

The Future is Now

But something else is happening to the grid as energy generation changes – the rise of microgrids. These smaller grid systems are linked to localised power sources, often referred to as “distributed generation” sources. For example, a handful of buildings in a city with their own solar panels might be connected to nearby residences.

In fact, that is exactly the model that LO3 Energy has experimented with in its Brooklyn Microgrid project. Customers signed up to it can choose to power their homes via a range of local renewable energy sources. People with their own solar panels can sell surplus electricity to their neighbours, for example. It’s a peer-to-peer network for electricity.

To ensure that accurate records of these transactions are kept, LO3 has opted to use blockchain distributed ledger technology. This means the microgrid’s accounting is decentralised and shared by everyone on the network.

“It’s virtually unhackable,” says founder and chief executive Lawrence Orsini, explaining that tampering with these records is almost impossible because of the fact that everyone has their own, regularly updated copy of the ledger.

LO3 is now rapidly expanding with a series of other projects around the world. One is based in South Australia, where Orsini explains there is already a lot of distributed generation going on – and plenty of grid stability issues. Users can now experiment with LO3 to get access to electricity from solar-fuelled batteries nearby when needed. (3)

Physical and Virtual Microgrids

Challenging the traditional electrical supply model are microgrids. The “microgrid” term normally refers to a localised grid that can disconnect from the main grid and operate autonomously. It uses local sources of energy to serve local users, integrating the supply of energy from various producers, including local power generators and providers of renewable energy such as solar power. Consumers with their own energy production capabilities (wind turbines or solar energy systems) can sell their surplus energy production back to peers in the microgrid, on a pay-per-use basis (becoming ‘prosumers’).

While physical microgrids are still rare, we do observe the development of virtual microgrids using peer-to-peer energy trading. Blockchain is just one element in the transformation of electricity supply, providing Distributed Ledger Technology (DLT) to members of a peer-to-peer energy network, or microgrid. It offers [or ‘provides’] a reliable, lower-cost digital platform for making, validating, recording and settling energy transactions in real time across a localised and decentralised energy system.

With increasing demand for more flexible energy supplies we expect a continued increase in the number of virtual microgrids and a gradual movement towards true, physical microgrids along 4 stages […] (4)

“This project…, is the first version of a new kind of energy market, operated by consumers, which will change the way we generate and consume electricity.”
New Scientist (5)

References:  

  1. microgrid-as-a-service-maas-and-the-blockchain/
  2. smart-grids-and-energy-storage-microgrid-in-brooklyn
  3. http://www.wired.co.uk/article/microgrids-wired-energy
  4. energy-and-resources/articles/will-microgrids-transform-the-marke.html
  5. http://brooklynmicrogrid.com/

Microgrid as a Service (MaaS) and the Blockchain

It is a splendid event to observe when two new technologies combine to create a new marketplace. In recent years as new sources of distributed energy have been entering the electrical grid to provide power they are necessitating a change to the existing large-scale infrastructure model of power supply.

Classic Electric Power Grid Model

Figure 1. Classic electric power grid model with bulk generators transferring power long distances to reach the consumer.  Image courtesy of NetGain Energy Advisors. (1)

The old model utility was large and centralized and tracking transactions was simple as consumers were on one side of the ledger, while the provider as on the other. And whereby currency and energy flowed only in opposite directions between two identified parties, consumer and provider.

In the emerging markets of small-scale independent energy providers, we can see buildings, communities and even individual residences having built capacity to provide intermittently or on demand power at times, and consume or store power from the grid at other times. Solar power is only available during the day, and will require new commercial methods of energy storage.

How-Microgrids-Work

Figure 2. An example Microgrid (2)

In the transition from decentralized utility is the development of the Micro-grid.  The Micro-grid offers many benefits to society, including; (a) use of renewable energy sources that reduce or eliminate the production of GHG’s, (b) increases in energy efficiency of energy transmission due to shortening of transmission distances and infrastructure, (c) improved municipal resilience against disaster and power reductions, and finally, (d) promotion of economic activity that improves universal standard of living.

As buildings and communities evolve they are moving toward renewable energy sources to supplement their energy requirements and reduce operating costs. Even the building codes are getting into the act, requiring buildings be constructed to new energy efficiency standards. Also, we are seeing the development of new technologies and business methods, such as solar powered charging stations for electric vehicles.

The existing electrical grid and utility model has to develop and adapt to these new technologies and means of locally generating power. The future will include the development and incorporation of peer to peer networks and alternative energy supply methods. Consumers may purchase power from multiple sources, and produce power and supply it to other users via the electrical grid.

Micro-grid and the Blockchain

As new energy sources/providers emerge there is added complexity to the network. Consumers of power can also be an energy providers, as well as having different energy sources available. This increased functionality raises the complexity of possible transactions in the network.

Imagine a financial ledger, where each user in the system is no longer constrained to be a consumer, but also a supplier to other users in the system. In order to track both the credits and debits it has been proposed that the exchange of blockchain tokens be utilized to sort out complicated energy transfer transactions in a distributed P2P network.

P2P TRADING

This class of Platform Application gives retailers the ability to empower consumers (or in an unregulated environment, the consumers themselves) to simply trade electricity with one another and receive payment in real-time from an automated and trustless reconciliation and settlement system. There are many other immediate benefits such as being able to select a clean energy source, trade with neighbors, receive more money for excess power, benefit from transparency of all your trades on a blockchain and very low-cost settlement costs all leading to lower power bills and improved returns for investments in distributed renewables. (3)

One blockchain based energy token that has caught my attention is called POWR and is currently in pre-ICO sales of the tokens by the Australian platform Power Ledger. One of the uses of the platform that is being suggested is peer to peer trading.

 “We are absolutely thrilled with the results of the public presale,” says Dr Jemma Green, co-founder and chair of Power Ledger. “Selling out in just over 3 days is a very strong performance in line with global ICO standards, which speaks to the strong levels of interest from consumer and institutional buyers.”

The proceeds from the total pre sale were AU$17 million and the main sale on Friday offers approximately 150 million POWR tokens (subject to final confirmation before the sale opens) in an uncapped sale, meaning that the level of market demand will have set the final token price at the end of the sale. (4)

 

References

  1. The Changing Power Landscape
  2. Siemens – Microgrid Solutions
  3. Power Ledger Applications
  4. PRESS RELEASE Having Closed $17M In Their Presale ICO, Power Ledger Confirm Their Public Sale Will Commence on 8th September 2017

A Modern Renaissance of Electrical Power: Microgrid Technology – Part 1

NYC First Power Grid - Edison #2.png

Figure 1:  The original Edison DC microgrid in New York City, which started operation on September 4, 1882 (1)

A.  Historical Development of Electric Power in the Metropolitan City

The development of electricity for commercial, municipal and industrial use developed at a frantic pace in the mid to late 1800’s and early 1900’s.  The original distribution system consisted of copper wiring laid below the streets of New York’s east side.  The first power plants and distribution systems were small compared to today’s interconnected grids which span nations and continents.  These small “islands” of electrical power were the original microgrids.  In time they grew to become the massive infrastructure which delivers us electrical power we have become dependent upon for the operation of our modern society.

1) Let There Be Light! – Invention of the Light Bulb

When electricity first came on the scene in the 1800’s it was a relatively unknown force. Distribution systems from a central plant were a new concept originally intended to provide electric power for the newly invented incandescent light bulb.  Thomas Edison first developed a DC power electric grid to test out and prove his ideas in New York, at the Manhattan Pearl Street Station in the 1870’s.  This first “microgrid” turned out to be a formidable undertaking.

[…] Edison’s great illumination took far longer to bring about than he expected, and the project was plagued with challenges. “It was massive, all of the problems he had to solve,” says writer Jill Jonnes, author of Empires of Light: Edison, Tesla, Westinghouse, and the Race to Electrify the World, to PBS. For instance, Edison had to do the dirty work of actually convincing city officials to let him use the Lower East Side as a testing ground, which would require digging up long stretches of street to install 80,000 feet insulated copper wiring below the surface.

He also had to design all of the hardware that would go into his first power grid, including switchboards, lamps, and even the actual meters used to charge specific amounts to specific buildings. That included even the six massive steam-powered generators—each weighing 30 tons—which Edison had created to serve this unprecedented new grid, according to IEEE. As PBS explains, Edison was responsible for figuring out all sorts of operational details of the project—including a “bank of 1,000 lamps for testing the system:” (1)

Although Edison was the first to develop a small DC electrical distribution system in a city, there was competition between DC and AC power system schemes in the early years of electrical grid development.  At the same time, there were a hodge-podge of other power sources and distribution methods in the early days of modern city development.

In the 1880s, electricity competed with steam, hydraulics, and especially coal gas. Coal gas was first produced on customer’s premises but later evolved into gasification plants that enjoyed economies of scale. In the industrialized world, cities had networks of piped gas, used for lighting. But gas lamps produced poor light, wasted heat, made rooms hot and smoky, and gave off hydrogen and carbon monoxide. In the 1880s electric lighting soon became advantageous compared to gas lighting. (2)

2) Upward Growth – Elevators and Tall Buildings

Another innovation which had been developing at the same time as electrical production and distribution, was the elevator, a necessity for the development of tall buildings and eventually towers and skyscrapers .  While there are ancient references to elevating devices and lifts, the original electric elevator was first introduced in Germany in 1880 by Werner von Siemens (3).  It was necessary for upward growth in urban centers that a safe and efficient means of moving people and goods was vital for the development of tall buildings.

Later in the 1800s, with the advent of electricity, the electric motor was integrated into elevator technology by German inventor Werner von Siemens. With the motor mounted at the bottom of the cab, this design employed a gearing scheme to climb shaft walls fitted with racks. In 1887, an electric elevator was developed in Baltimore, using a revolving drum to wind the hoisting rope, but these drums could not practically be made large enough to store the long hoisting ropes that would be required by skyscrapers.

Motor technology and control methods evolved rapidly. In 1889 came the direct-connected geared electric elevator, allowing for the building of significantly taller structures. By 1903, this design had evolved into the gearless traction electric elevator, allowing hundred-plus story buildings to become possible and forever changing the urban landscape. Multi-speed motors replaced the original single-speed models to help with landing-leveling and smoother overall operation.

Electromagnet technology replaced manual rope-driven switching and braking. Push-button controls and various complex signal systems modernized the elevator even further. Safety improvements have been continual, including a notable development by Charles Otis, son of original “safety” inventor Elisha, that engaged the “safety” at any excessive speed, even if the hoisting rope remained intact. (4)

The-Story-In-Elevators-And-Escalators-274

Figure 2:  The Woolworth Building at 233 Broadway, Manhattan, New York City – The World’s Tallest Building, 1926 (5)

3) Hydroelectric A/C Power – Tesla, Westinghouse and Niagara Falls

Although Niagara Falls was not the first hydroelectric project it was by far the largest and from the massive power production capacity spawned a second Industrial Revolution.

“On September 30, 1882, the world’s first hydroelectric power plant began operation on the Fox River in Appleton, Wisconsin. […] Unlike Edison’s New York plant which used steam power to drive its generators, the Appleton plant used the natural energy of the Fox River. When the plant opened, it produced enough electricity to light Rogers’s home, the plant itself, and a nearby building. Hydroelectric power plants of today generate a lot more electricity. By the early 20th century, these plants produced a significant portion of the country’s electric energy. The cheap electricity provided by the plants spurred industrial growth in many regions of the country. To get even more power out of the flowing water, the government started building dams.” (6)

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Figure 3:  The interior of Power House No. 1 of the Niagara Falls Power Company (1895-1899) (7)

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Figure 4:  Adam’s power station with three Tesla AC generators at Niagara Falls, November 16, 1896. (7)

Electrical Transmission, Tesla and the Polyphase Motor

The problem of the best means of transmission, though, would be worked out not by the commission but in the natural course of things, which included great strides in the development of AC. In addition, the natural course of things included some special intervention from on high (that is, from Edison himself).

But above all, it involved Tesla, probably the only inventor ever who could be put in a class with Edison’s in terms of the number and significance of his innovations. The Croatian-born scientific mystic–he spoke of his insight into the mechanical principles of the motor as a kind of religious vision–had once worked for Edison. He had started out with the Edison Company in Paris, where his remarkable abilities were noticed by Edison’s business cohort and close friend Charles Batchelor, who encouraged Tesla to transfer to the Edison office in New York City, which he did in 1884. There Edison, too, became impressed with him after he successfully performed a number of challenging assignments. But when Tesla asked Edison to let him undertake research on AC–in particular on his concept for an AC motor–Edison rejected the idea. Not only wasn’t Edison interested in motors, he refused to have anything to do with the rival current.

So for the time being Tesla threw himself into work on DC. He told Edison he thought he could substantially improve the DC dynamo. Edison told him if he could, it would earn him a $50,000 bonus. This would have enabled Tesla to set up a laboratory of his own where he could have pursued his AC interests. By dint of extremely long hours and diligent effort, he came up with a set of some 24 designs for new equipment, which would eventually be used to replace Edison’s present equipment.

But he never found the promised $50,000 in his pay envelope. When he asked Edison about this matter, Edison told him he had been joking. “You don’t understand American humor,” he said. Deeply disappointed, Tesla quit his position with the Edison company, and with financial backers, started his own company, which enabled him to work on his AC ideas, among other obligations.

The motor Tesla patented in 1888 is known as the induction motor. It not only provided a serviceable motor for AC, but the induction motor had a distinct advantage over the DC motor. (About two-thirds of the motors in use today are induction motors.)

The idea of the induction motor is simplicity itself, based on the Faraday principle. And its simplicity is its advantage over the DC motor.

An electrical motor–whether DC or AC–is a generator in reverse. The generator operates by causing a conductor (armature) to move (rotate) in a magnetic field, producing a current in the armature. The motor operates by causing a current to flow in an armature in a magnetic field, producing rotation of the armature. A generator uses motion to produce electricity. A motor uses electricity to produce motion.

The DC motor uses commutators and brushes (a contact switching mechanism that opens and closes circuits) to change the direction of the current in the rotating armature, and thus sustain the direction of rotation and direction of current.

In the AC induction motor, the current supply to the armature is by induction from the magnetic field produced by the field current.  The induction motor thus does away with the troublesome commutators and brushes (or any other contact switching mechanism). However, in the induction motor the armature wouldn’t turn except as a result of rotation of the magnetic field, which is achieved through the use of polyphase current. The different current phases function in tandem (analogous to pedals on a bicycle) to create differently oriented magnetic fields to propel the armature.  

Westinghouse bought up the patents on the Tesla motors almost immediately and set to work trying to adapt them to the single-phase system then in use. This didn’t work. So he started developing a two-phase system. But in December 1890, because of the company’s financial straits–the company had incurred large liabilities through the purchase of a number of smaller companies, and had to temporarily cut back on research and development projects–Westinghouse stopped the work on polyphase. (8)

4) The Modern Centralized Electric Power System

After the innovative technologies which allowed expansion and growth within metropolitan centers were developed there was a race to establish large power plants and distribution systems from power sources to users.  Alternating Current aka AC power was found to the preferred method of power transmission over copper wires from distant sources.  Direct Current power transmission proved problematic over distances, generated resistance heat resulting in line power losses. (9)

440px-New_York_utility_lines_in_1890

Figure 5:  New York City streets in 1890. Besides telegraph lines, multiple electric lines were required for each class of device requiring different voltages (11)

AC has a major advantage in that it is possible to transmit AC power as high voltage and convert it to low voltage to serve individual users.

From the late 1800s onward, a patchwork of AC and DC grids cropped up across the country, in direct competition with one another. Small systems were consolidated throughout the early 1900s, and local and state governments began cobbling together regulations and regulatory groups. However, even with regulations, some businessmen found ways to create elaborate and powerful monopolies. Public outrage at the subsequent costs came to a head during the Great Depression and sparked Federal regulations, as well as projects to provide electricity to rural areas, through the Tennessee Valley Authority and others.

By the 1930s regulated electric utilities became well-established, providing all three major aspects of electricity, the power plants, transmission lines, and distribution. This type of electricity system, a regulated monopoly, is called a vertically-integrated utility. Bigger transmission lines and more remote power plants were built, and transmission systems became significantly larger, crossing many miles of land and even state lines.

As electricity became more widespread, larger plants were constructed to provide more electricity, and bigger transmission lines were used to transmit electricity from farther away. In 1978 the Public Utilities Regulatory Policies Act was passed, making it possible for power plants owned by non-utilities to sell electricity too, opening the door to privatization.

By the 1990s, the Federal government was completely in support of opening access to the electricity grid to everyone, not only the vertically-integrated utilities. The vertically-integrated utilities didn’t want competition and found ways to prevent outsiders from using their transmission lines, so the government stepped in and created rules to force open access to the lines, and set the stage for Independent System Operators, not-for-profit entities that managed the transmission of electricity in different regions.

Today’s electricity grid – actually three separate grids – is extraordinarily complex as a result. From the very beginning of electricity in America, systems were varied and regionally-adapted, and it is no different today. Some states have their own independent electricity grid operators, like California and Texas. Other states are part of regional operators, like the Midwest Independent System Operator or the New England Independent System Operator. Not all regions use a system operator, and there are still municipalities that provide all aspects of electricity. (10)

 

800px-Electricity_grid_simple-_North_America.svg.png

Figure 6:  Diagram of a modern electric power system (11)

A Brief History of Electrical Transmission Development

The first transmission of three-phase alternating current using high voltage took place in 1891 during the international electricity exhibition in Frankfurt. A 15,000 V transmission line, approximately 175 km long, connected Lauffen on the Neckar and Frankfurt.[6][12]

Voltages used for electric power transmission increased throughout the 20th century. By 1914, fifty-five transmission systems each operating at more than 70,000 V were in service. The highest voltage then used was 150,000 V.[13] By allowing multiple generating plants to be interconnected over a wide area, electricity production cost was reduced. The most efficient available plants could be used to supply the varying loads during the day. Reliability was improved and capital investment cost was reduced, since stand-by generating capacity could be shared over many more customers and a wider geographic area. Remote and low-cost sources of energy, such as hydroelectric power or mine-mouth coal, could be exploited to lower energy production cost.[3][6]

The rapid industrialization in the 20th century made electrical transmission lines and grids a critical infrastructure item in most industrialized nations. The interconnection of local generation plants and small distribution networks was greatly spurred by the requirements of World War I, with large electrical generating plants built by governments to provide power to munitions factories. Later these generating plants were connected to supply civil loads through long-distance transmission. (11)

 

To be continued in Part 2:  Distributed Generation and The Microgrid Revolution

 

References:

  1. The Forgotten Story Of NYC’s First Power Grid  by Kelsey Campbell-Dollaghan
  2. The Electrical Grid – Wikipedia
  3. The History of the Elevator – Wikipedia
  4. Elevator History – Columbia Elevator
  5. The History of Elevators and Escalators – The Wonder Book Of Knowledge | by Henry Chase (1921)
  6. The World’s First Hydroelectric Power Station
  7. Tesla Memorial Society of New York Website 
  8. The Day They Turned The Falls On: The Invention Of The Universal Electrical Power System by Jack Foran
  9. How electricity grew up? A brief history of the electrical grid
  10. The electricity grid: A history
  11. Electric power transmission

Hybrid Electric Buildings; A New Frontier for Energy and Grids

.OneMaritimePlaza-300x225 PeakerPlantSanFranHybrid Electric Buildings are the latest in developments for packaged energy storage in buildings which offer several advantages including long-term operational cost savings. These buildings have the flexibility to combine several technologies and energy sources in with a large-scale integrated electric battery system to operate in a cost-effective manner.

San Francisco’s landmark skyscraper, One Maritime Plaza, will become the city’s first Hybrid Electric Building using Tesla Powerpack batteries. The groundbreaking technology upgrade by Advanced Microgrid Solutions (AMS) will lower costs, increase grid and building resiliency, and reduce the building’s demand for electricity from the sources that most negatively impact the environment.

Building owner Morgan Stanley Real Estate Investing hired San Francisco-based AMS to design, build, and operate the project. The 500 kilowatt/1,000 kilowatt-hour indoor battery system will provide One Maritime Plaza with the ability to store clean energy and control demand from the electric grid. The technology enables the building to shift from grid to battery power to conserve electricity in the same way a hybrid-electric car conserves gasoline. (1)

In addition to storage solutions these buildings can offer significant roof area to install solar panel modules and arrays to generate power during the day.  Areas where sunshine is plentiful and electricity rates are high, solar PV and storage combinations for commercial installations are economically attractive.

For utility management, these systems are ideal in expansion of the overall grid, as more micro-grids attach to the utility infrastructure overall supply and resiliency is improved.

In recent developments AMS has partnered with retailer Wal-Mart to provide on-site and “behind the meter” energy storage solutions for no upfront costs.

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Figure 2.  Solar Panels on Roof of Wal-Mart, Corporate Headquarters, Puerto Rico (3)

On Tuesday, the San Francisco-based startup announced it is working with the retail giant to install behind-the-meter batteries at stores to balance on-site energy and provide megawatts of flexibility to utilities, starting with 40 megawatt-hours of projects at 27 Southern California locations.

Under the terms of the deal, “AMS will design, install and operate advanced energy storage systems” at the stores for no upfront cost, while providing grid services and on-site energy savings. The financing was made possible by partners such as Macquarie Capital, which pledged $200 million to the startup’s pipeline last year.

For Wal-Mart, the systems bring the ability to shave expensive peaks, smooth out imbalances in on-site generation and consumption, and help it meet a goal of powering half of its operations with renewable energy by 2025. Advanced Microgrid Solutions will manage its batteries in conjunction with building load — as well as on-site solar or other generation — to create what it calls a “hybrid electric building” able to keep its own energy costs to a minimum, while retaining flexibility for utility needs.

The utility in this case is Southern California Edison, a long-time AMS partner, which “will be able to tap into these advanced energy storage systems to reduce demand on the grid as part of SCE’s groundbreaking grid modernization project,” according to Tuesday’s statement. This references the utility’s multibillion-dollar grid modernization plan, which is now before state regulators.  (2)

References:

  1. San Francisco’s First Hybrid Electric Building – Facility Executive, June 28, 2016
    https://facilityexecutive.com/2016/06/skyscraper-will-be-san-franciscos-first-hybrid-electric-building/

  2. Wal-Mart, Advanced Microgrid Solutions to Turn Big-Box Stores Into Hybrid Electric Buildings, GreenTech Media, April 11, 2017  https://www.greentechmedia.com/articles/read/wal-mart-to-turn-big-box-stores-into-hybrid-electric-buildings?utm_source=Daily&utm_medium=Newsletter&utm_campaign=GTMDaily

  3. Solar Panels on Wal-Mart Roof  http://corporate.walmart.com/_news_/photos/solar-panels-roof-puerto-rico

Flow Batteries: Developments in Energy Storage Systems (ESS)

The need for large scale storage solutions come to the forefront as a means to adjust supply to demand on the electrical grid.  Energy storage systems can adjust time of delivery to eliminate the need for peaker plants, allow for the addition of intermittent renewable energy sources such as wind and solar, or allow for large users to reduce facility operating costs by using a storage system to supplement energy supply reducing peak demand, most notably for summer A/C loads in buildings.

vanadium-flow-battery-wind-energy

Out of engineering research laboratories in materials science and electro-chemistry  are coming new energy storage systems designed for the future to solve these issues meanwhile opening up new enterprises and industry.  The characteristics of an ideal flow battery would include:  a long service life, modularity and scalability, no standby losses, chargeability, low maintenance, and safe.  In addition a flow battery will have to be economic compared to other systems which will need to be determined using LCOE analysis.

Related Articles:

  1. https://duanetilden.com/2015/01/27/determining-the-true-cost-lcoe-of-battery-energy-storage/
  2. https://duanetilden.com/2015/01/26/what-is-levelized-cost-of-energy-or-lcoe/
  3. https://duanetilden.com/2016/01/18/energy-storage-compared-to-conventional-resources-using-lcoe-analysis/
  4. https://duanetilden.com/2015/02/17/vanadium-flow-battery-competes-with-lithium-and-lead-acid-at-grid-scale/ 

Links:

 

 

The Smart Grid – Modern Electrical Infrastructure

When we talk about the emerging Smart Grid there comes with the topic an array of exciting and new technologies; Micro-Grids, Distributed Generation, Smart Meters, Load Shifting, Demand Response, Electric Vehicles with Battery Storage for Demand Response, and more.  Recent development in Renewable Energy sources has been driven by concerns over Climate Change, allowing for unprecedented growth in residential and commercial PV Solar Panel installations.

redwoodhighschool.jpg

Figure 1:  Redwood High School in Larkspur, CA installed a 705kW SunPower system that’s projected to save $250,000 annually. The carports include EV charging stations for four cars. (1)

Climate Change and burning of fossil fuels are hot topics in the world. Most recently the city of San Francisco has mandated the installation of solar panels on all new buildings constructed under 10 storeys, which will come into effect in 2017 as a measure to reduce carbon emissions.  Currently all new buildings in California are required to set aside 15% of roof area for solar. (2)

“Under existing state law, California’s Title 24 Energy Standards require 15% of roof area on new small and mid-sized buildings to be “solar ready,” which means the roof is unshaded by the proposed building itself, and free of obtrusions. This state law applies to all new residential and commercial buildings of 10 floors or less.

Supervisor Wiener’s ordinance builds on this state law by requiring this 15% of “solar ready” roof area to have solar actually installed. This can take the form of either solar photovoltaic or solar water panels, both of which supply 100% renewable energy.” (3)

Weather and Aging Infrastructure:

Despite an increasing abundance of energy-efficient buildings and other measures, electricity demand has risen by around 10% over the last decade, partly driven by the massive growth of digital device usage and the expanding demand for air conditioning, as summers continue to get hotter in many states.

According to 2013 data from the Department of Energy (DOE), US power grid outages have risen by 285% since records on blackouts began in 1984, for the most part driven by the grid’s vulnerability to unusual and extreme weather events – such as the devastating Hurricane Sandy in 2012 that caused extensive power outages across the East Coast – which are becoming less unusual as the years roll on.

“We used to have two to five major weather events per year from the 50s to the 80s,” said University of Minnesota Professor of Electrical and Computer Engineering Massoud Amin in a 2014 interview with the International Business Times.

“Between 2008 and 2012, major outages caused by weather increased to 70 to 130 outages per year. Weather used to account for about 17% to 21% of all root causes. Now, in the last five years, it’s accounting for 68% to 73% of all major outages.” (4)

How is the Smart Grid so different from the traditional electrical grid?

The established model of providing power to consumers involves the supply of electricity generated from a distant source and transmitted at high voltage to sub-stations local to the consumer, refer to Figure 2.  The power plants that generate the electricity are mostly thermo-electric (coal, gas and nuclear power), with some hydro-electric sources (dams and reservoirs) and most recently wind farms and large solar installations.

“The national power grid that keeps America’s lights on is a massive and immensely valuable asset. Built in the decades after the Second World War and valued today at around $876bn, the country’s grid system as a whole connects electricity from thousands of power plants to 150 million customers through more than five million miles of power lines and around 3,300 utility companies.” (4)

power_fig1 Old Grid Model.gif

Figure 2:  Existing Transmission and Distribution Grid Structure within the Power Industry (5)

The (Transmission & Distribution) market supplies equipment, services and production systems for energy markets. The initial stage in the process is converting power from a generation source (coal, nuclear, wind, etc.) into a high voltage electrical format that can be transported using the power grid, either overhead or underground. This “transformation” occurs very close to the source of the power generation.

The second stage occurs when this high-voltage power is “stepped-down” by the use of switching gears and then controlled by using circuit breakers and arresters to protect against surges. This medium voltage electrical power can then be safely distributed to urban or populated areas.

The final stage involves stepping the power down to useable voltage for the commercial or residential customer.  In short, while power generation relates to the installed capacity to produce energy from an organic or natural resource, the T&D space involves the follow up “post-power generation production” as systems and grids are put in place to transport this power to end users. (5)

The Smart Grid is an evolution in multiple technologies which in cases is overlaying or emerging from the existing grid.  New generating facilities such as wind power or solar installations which may be small or local to a municipal or industrial user are being tied into the existing grid infra-structure.  In some cases residential PV Solar systems are being tied into the Grid with some form of agreement to purchase excess energy, in some cases at rates favorable to the installer, depending on the utility and region.

Another characteristic of the evolving Smart Grid is in communication technology and scalability.  Use of wifi protocols for communication between parts of the system allow for new processes and access to resources which were previously unavailable.  Ability to control systems to defer demand to non-peak hours within a building as one example.

Microgrids, smaller autonomous systems servicing a campus of buildings or larger industry,  may plug into a larger City-wide Smart Grid in a modular manner.  In the event of a catastrophic event such as a hurricane or earthquake the Smart Grid offers users resiliency through multiple sources of energy supply.

Distributed Generation includes a number of different and smaller scale energy sources into the mix.  The newer, small scale Renewable Energy projects which are being tied to the electrical grid as well as other technologies such as Co-Generation, Waste To Energy facilities, Landfill Gas Systems, Geothermal and the like.  As growth continues there needs to be ways to control and manage these multiple energy sources into the grid.  Also increased needs to maintain privacy, isolate and control systems, and prevent unauthorized access and control.  This is leading to growth in  Energy Management and Security Systems.

ARES-rail-train

Figure 3:  An artist’s rendering of the massive rail used in the ARES power storage project to store renewable energy as gravitational potential energy. Source: ARES North America (6)

Energy Storage is emerging as necessary in the Smart Grid due to fluctuations in source supply of energy, especially Solar and Wind Power, and the intermittent and cyclical nature of user demand.   The existing grid does not have the need for energy storage systems as energy sources were traditionally large power stations which generally responded to anticipated need during the course of the day.

As more Renewable Energy systems go online the need for storage will grow.  Energy Storage in its various forms will also enable Load Shifting or Peak Shaving strategies for economic gains in user operations.  These strategies are already becoming commercially available for buildings to save the facility operators rate charges by limiting demand during peak periods at higher utility rates.

RTEmagicC_CSE1412_MAG_PP_FENERGY_Figure_1.jpg

Figure 4:  Effect of Peak Shaving using Energy Storage  (6) 

Peak-load shifting is the process of mitigating the effects of large energy load blocks during a period of time by advancing or delaying their effects until the power supply system can readily accept additional load. The traditional intent behind this process is to minimize generation capacity requirements by regulating load flow. If the loads themselves cannot be regulated, this must be accomplished by implementing energy storage systems (ESSs) to shift the load profile as seen by the generators (see Figure 4).

Depending on the application, peak-load shifting can be referred to as “peak shaving” or “peak smoothing.” The ESS is charged while the electrical supply system is powering minimal load and the cost of electric usage is reduced, such as at night. It is then discharged to provide additional power during periods of increased loading, while costs for using electricity are increased. This technique can be employed to mitigate utility bills. It also effectively shifts the impact of the load on the system, minimizing the generation capacity required. (6)

Challenges with chemical storage systems such as batteries are scale and cost.  Currently pumped hydro is the predominant method of storing energy from intermittent sources providing 99% of global energy storage. (7)

inline_demandresponse

Figure 5:  Actual Savings accrued due to Demand Response Program  (8) 

Demand Response (DR) is another technology getting traction in the Smart Grid economy. As previously mentioned Energy Management and Security Systems are “…converging with Energy Storage technology to make DR a hot topic.  First, the tools necessary to determine where energy is being stored, where it is needed and when to deliver it is have developed over decades in the telecommunications sector.  Secondly, the more recent rush of advanced battery research is making it possible to store energy and provide the flexibility necessary for demand response to really work. Mix that with the growing ability to generate energy on premises through solar, wind and other methods (Distributed Generation) and a potent new distributed structure is created.” (9)

Demand response programs provide financial incentives to reduce energy consumption during peak periods of energy demand. As utilities and independent system operators (ISOs) are pressured to keep costs down and find ways to get as many miles as they can out of every kilowatt, demand response programs have gained popularity. (8)

VirtualPowerPlant#1

Figure 6:  The Demonstration Project 2’s Virtual Power Plant (10) 

Virtual Power Plant: When an increasing share of energy is produced by renewable sources such as solar and wind, electricity production can fluctuate significantly. In the future there will be a need for services which can help balance power systems in excess of what conventional assets will be able to provide. Virtual power plants (VPPs) are one of the most promising new technologies that can deliver the necessary stabilising services.  (11)

In the VPP model an energy aggregator gathers a portfolio of smaller generators and operates them as a unified and flexible resource on the energy market or sells their power as system reserve.

VPPs are designed to maximize asset owners’ profits while also balancing the grid. They can match load fluctuations through forecasting, advance metering and computerized control, and can perform real-time optimization of energy resources.

“Virtual power plants essentially represent an ‘Internet of Energy,’ tapping existing grid networks to tailor electricity supply and demand services for a customer,” said Navigant senior analyst Peter Asmus in a market report. The VPP market will grow from less than US $1 billion per year in 2013 to $3.6 billion per year by 2020, according to Navigant’s research — and one reason is that with more variable renewables on the grid flexibility and demand response are becoming more crucial.  (12)

How-Microgrids-Work.jpg

Figure 7:   Example of a Microgrid System With Loads, Generation, Storage and Coupling to a Utility Grid (13)

Microgrids:  Microgrids are localized grids that can disconnect from the traditional grid to operate autonomously and help mitigate grid disturbances to strengthen grid resilience (14).  The structure of a microgrid is a smaller version of the smart grid formed in a recursive  hierarchy where multiple local microgrids may interconnect to form the larger smart grid which services a region or community.

Summary:

The convergence of aging existing infrastructure, continued growth in populations and electrical demand and concerns over climate change have lead to the emerging smart grid and it’s array of new technologies.  This trend is expected to continue as new growth and replacement will be necessary for an aging electrical grid system, from the larger scope transmission systems and utilities, to smaller scale microgrids.  These systems will become integrated and modular, almost plug-and-play, with inter-connectivity and control through wireless internet protocols.

References:

  1. https://cleanpowermarketinggroup.com/category/blog/
  2. http://www.npr.org/sections/thetwo-way/2016/04/20/474969107/san-francisco-requires-new-buildings-to-install-solar-panels
  3. https://medium.com/@Scott_Wiener/press-release-board-of-supervisors-unanimously-passes-supervisor-wiener-s-legislation-to-require-693deb9c2369#.3913ug8ph
  4. http://www.power-technology.com/features/featureupgrading-the-us-power-grid-for-the-21st-century-4866973/
  5. http://www.incontext.indiana.edu/2010/july-aug/article3.asp
  6. http://www.csemag.com/single-article/implementing-energy-storage-for-peak-load-shifting/95b3d2a5db6725428142c5a605ac6d89.html
  7. http://www.forbes.com/sites/jamesconca/2016/05/26/batteries-or-train-pumped-energy-for-grid-scale-power-storage/#30b5b497de55
  8. http://www.summitenergygps.com/optimize-rebates-incentives-credits.html
  9. https://duanetilden.com/2015/12/26/demand-response-energy-distribution-a-technological-revolution/
  10. https://hub.globalccsinstitute.com/publications/twenties-project-final-report-short-version/demonstration-project-2-large-scale-virtual-power-plant-integration-derint
  11. http://energy.gov/oe/services/technology-development/smart-grid/role-microgrids-helping-advance-nation-s-energy-system
  12. http://www.renewableenergyworld.com/articles/print/volume-16/issue-5/solar-energy/virtual-power-plants-a-new-model-for-renewables-integration.html
  13. http://w3.usa.siemens.com/smartgrid/us/en/microgrid/pages/microgrids.aspx
  14. http://energy.gov/oe/services/technology-development/smart-grid/role-microgrids-helping-advance-nation-s-energy-system

Related Blog Posts:

Other Related Articles and Websites:

Leading Energy Storage Tech for Renewable Energy

ElectricityStorage

Image Source:  U.S. Energy Information Administration (1)

Summary

“It doesn’t always rain when you need water, so we have reservoirs – but we don’t have the same system for electricity,” says Jill Cainey, director of the UK’s Electricity Storage Network.

[…] Big batteries, whose costs are plunging, are leading the way. But a host of other technologies, from existing schemes like splitting water to create hydrogen,compressing air in underground caverns, flywheels and heated gravel pits, to longer term bets like supercapacitors and superconducting magnets, are also jostling for position.

In the UK, the first plant to store electricity by squashing air into a liquid is due to open in March, while the first steps have been taken towards a virtual power station comprised of a network of home batteries.

“We think this will be a breakthrough year,” says John Prendergast at RES, a UK company that has 80MW of lithium-ion battery storage operational across the world and six times more in development, including its first UK project at a solar park near Glastonbury. “All this only works if it reduces costs for consumers and we think it does,” he says.

Energy storage is important for renewable energy not because green power is unpredictable – the sun, wind and tides are far more predictable than the surge that follows the end of a Wimbledon tennis final or the emergency shutdown of a gas-fired power plant. Storage is important because renewable energy is intermittent: strong winds in the early hours do not coincide with the peak demand of evenings. Storage allows electricity to be time-shifted to when it is needed, maximising the benefits of windfarms and solar arrays. (2)

 

References

(1) http://1.usa.gov/1UOayAh

(2) http://bit.ly/1UOaJvs

Supercritical CO2 Used For Solar Battery Power System

“GE has announced it is working on a way to use CO2 pollution to make new types of solar batteries that could each power up to 100,000 homes. CO2 is the main contributor to climate change, and is released into the atmosphere when coal is processed at power plants. Currently environmental procedures mean that some CO2 from these plants is captured and stored, so it’s not released back into the atmosphere. But the question has always been: What do you do with the stored gas?” (1)

 

dodge-sco23 supercritical CO2 turbine

Figure #1:  Comparison of 10 MWe Turbines (2)

What are the Benefits of Supercritical CO2?  With the transition from steam generation to using Supercritical CO2 as a working fluid, we seen large gains in energy efficiency conversion, coupled with significant size (footprint) reduction of turbomachines.  Other benefits include sequestering CO2 from the environment and reducing GHG emissions.   Also, this system can be utilized to capture energy from other heat sources including waste heat streams and co-generation applications. 

Supercritical CO2 image comparison

Figure 2:  Relative size  comparison of steam, helium and supercritical CO2 turbomachinery for Generation IV Nuclear Reactors (3)

What is Supercritical CO2?  “[…] Supercritical CO2 is a fluid state of carbon dioxide where it is held above its critical pressure and critical temperature which causes the gas to go beyond liquid or gas into a phase where it acts as both simultaneously. Many fluids can achieve supercritical states and supercritical steam has been used in power generation for decades. Supercritical CO2 has many unique properties that allow it to dissolve materials like a liquid but also flow like a gas. sCO2 is non-toxic and non-flammable and is used as an environmentally-friendly solvent for decaffeinating coffee and dry-cleaning clothes.

dodge-sco211 supercritical CO2 2

Figure 3:  CO2 phase diagram illustrating supercritical region. (4)

The use of sCO2 in power turbines has been an active area of research for a number of years, and now multiple companies are bringing early stage commercial products to market. The attraction to using sCO2 in turbines is based on its favorable thermal stability compared to steam which allows for much higher power outputs in a much smaller package than comparable steam cycles. CO2 reaches its supercritical state at moderate conditions and has excellent fluid density and stability while being less corrosive than steam.  The challenges in using sCO2 are tied to identifying the best materials that can handle the elevated temperatures and pressures, manufacturing turbo machinery, valves, seals, and of course, costs. […] ”  (2)

How will this work?

“[…] The design has two main parts. The first one collects heat energy from the sun and stores it in a liquid of molten salt. “This is the hot side of the solution,” Sanborn says. The other component uses surplus electricity from the grid to cool a pool of liquid CO2 so that it becomes dry ice.

During power generation, the salt releases the heat to expand the cold CO2 into a supercritical fluid, a state of matter where it no longer has specific liquid and gas phases. It allows engineers to make the system more efficient.

The supercritical fluid will flow into an innovative CO2 turbine called the sunrotor, which is based on a GE steam turbine design. Although the turbine can fit on an office shelf (see image above) it can generate as much as 100 megawatts of “fast electricity” per installed unit—enough to power 100,000 U.S. homes.

Sanborn believes that a large-scale deployment of the design would be able to store “significant amounts” of power —— and deliver it back to the grid when needed. “We’re not talking about three car batteries here,” he says. “The result is a high-efficiency, high-performance renewable energy system that will reduce the use of fossil fuels for power generation.”

He says the system could be easily connected to a solar power system or a typical gas turbine. The tanks and generators could fit on trailers. His goal is to bring the cost to $100 per megawatt-hour, way down from the $250 it costs to produce the same amount in a gas-fired power plant. “It is so cheap because you are not making the energy, you are taking the energy from the sun or the turbine exhaust, storing it and transferring it,” says Sanborn.

The process is also highly efficient, Sanborn says, yielding as much as 68 percent of the stored energy back to the grid. The most efficient gas power plants yield 61 percent. The team is now building a conceptual design, which Sanborn believes could take five to 10 years to get from concept to market. […]” (5)

Read more at:

1.  https://duanetilden.com/2013/10/29/supercritical-co2-refines-cogeneration-for-industry/

2. https://duanetilden.com/2013/10/29/supercritical-co2-turbine-for-power-production-waste-heat-energy-recovery/

3. https://duanetilden.com/2013/10/29/waste-heat-recovery-using-supercritical-co2-turbines-to-create-electrical-power/

4. https://duanetilden.com/2015/04/23/doe-invests-in-super-critical-carbon-dioxide-turbine-research-to-replace-steam-for-electric-power-generators/

 

References:

  1. http://www.fastcompany.com/3057630/fast-feed/ge-is-working-on-a-way-to-turn-co2-pollution-into-solar-batteries
  2. http://breakingenergy.com/2014/11/24/supercritical-carbon-dioxide-power-cycles-starting-to-hit-the-market/
  3. http://large.stanford.edu/courses/2014/ph241/dunham1/
  4. https://commons.wikimedia.org/wiki/File:Carbon_dioxide_pressure-temperature_phase_diagram.svg
  5. http://www.vanguardngr.com/2016/03/ge-report-this-scientist-has-turned-the-tables-on-greenhouse-gas-using-co2-to-generate-clean-electricity/

 

DOE’s 3 Year $220M Grid Modernization Plan

With 88 projects from coast to coast, it might be the biggest grid edge R&D effort ever. Here’s how the money is going to be spent.

Sourced through Scoop.it from: www.greentechmedia.com

“[…] The Grid Modernization Multi-Year Program Plan will bring a consortium of 14 national laboratories together with more than 100 companies, utilities, research organizations, state regulators and regional grid operators. The scope of this work includes integrating renewable energy, energy storage and smart building technologies at the edges of the grid network, at a much greater scale than is done today.

That will require a complicated mix of customer-owned and utility-controlled technology, all of which must be secured against cyberattacks and extreme weather events. And at some point, all of this new technology will need to become part of how utilities, grid operators, regulators, ratepayers and new energy services providers manage the economics of the grid.

DOE has already started releasing funds to 10 “pioneer regional partnerships,” or “early-stage, public-private collaborative projects […]  The projects range from remote microgrids in Alaska and grid resiliency in New Orleans, to renewable energy integration in Vermont and Hawaii, and scaling up to statewide energy regulatory overhauls in California and New York. Others are providing software simulation capabilities to utilities and grid operators around the country, or looking at ways to tie the country’s massive eastern and western grids into a more secure and efficient whole.

Another six “core” projects are working on more central issues, like creating the “fundamental knowledge, metrics and tools we’re going to need to establish the foundation of this effort,” he said (David Danielson).  Those include technology architecture and interoperability, device testing and validation, setting values for different grid services that integrated distributed energy resources (DERs) can provide, and coming up with the right sensor and control strategy to balance costs and complexity.

Finally, the DOE has identified six “cross-cutting” technology areas that it wants to support, Patricia Hoffman, assistant secretary of DOE’s Office of Electricity Delivery and Energy Reliability, noted in last week’s conference call. Those include device and integrated system testing, sensing and measurement, system operations and controls, design and planning tools, security and resilience, and institutional support for the utilities, state regulators and regional grid operators that will be the entities that end up deploying this technology at scale.

Much of the work is being driven by the power grid modernization needs laid out in DOE’s Quadrennial Energy Review, which called for $3.5 billion in new spending to modernize and strengthen the country’s power grid, while the Quadrennial Technology Review brought cybersecurity and interoperability concerns to bear.[…]

DOE will hold six regional workshops over the coming months to provide more details, Danielson said. We’ve already seen one come out this week — the $18 million in SunShot grants for six projects testing out ways to bring storage-backed solar power to the grid at a cost of less than 14 cents per kilowatt-hour.

“We can’t look at one attribute of the grid at a time,” he said. “We’re not just looking for a secure grid — we’re looking for an affordable grid, a sustainable grid, a resilient grid.” And one that can foster renewable energy and greenhouse gas reduction at the state-by-state and national levels. […]

See on Scoop.itGreen Energy Technologies & Development