Measuring and Monitoring Energy Efficiency

Defining Energy Efficiency

To begin, let us ask what is energy efficiency, what are it’s components and how is it measured.  To make comparisons we need to gather data using measures relevant to the industry in question, also to the input forms of energy, waste streams and the useful work performed.  In the case of a building we may use meters to measure consumption or utility bills and compare changes in consumption rates over time.

To an engineer, energy efficiency is the ratio of useful work over total energy input.  For example, a room air conditioner’s efficiency is measured by the energy efficiency ratio (EER). The EER is the ratio of the cooling capacity (in British thermal units [Btu] per hour) to the power input (in watts).

On a grander scale we may be looking improvements over an industry or sector, changing fuel types in a utility such as the conversion of a coal plant to the production of power fueled by natural gas to reduce the carbon load on the environment.  Efficiency may be measured by different metrics depending on the result sought and may include the environmental impact of waste streams.

EnergyEfficientEconomy

Figure 1:  Historical Energy Use Graph  (1)

Whatever the exact yearly investment figure, the historical economic impact of efficiency is quite clear. As the graph () shows, efficiency has provided three times more of the economic services than new production since 1970:

The blue line illustrates demand for energy services (the economic activity associated with energy use) since 1970; the solid red line shows energy use; and the green line illustrates the gain in energy efficiency. While demand for energy services has tripled in the last four decades, actual energy consumption has only grown by 40 percent. Meanwhile, the energy intensity of our economy has fallen by half.

The area between the solid red line and the blue line represents the amount of energy we did not need to consume since 1970; the area between the dashed red line and the solid red line indicates how much energy we consumed since 1970.

The chart shows that energy efficiency met nearly three quarters of the demand for services, while energy supply met only one quarter.

“One immediate conclusion from this assessment is that the productivity of our economy may be more directly tied to greater levels of energy efficiency rather than a continued mining and drilling for new energy resources,” wrote Laitner. (1)

As noted in an article by the EIA;  The central question in the measurement of energy efficiency may really be “efficient with respect to what?” (2)  In general terms when discussing energy efficiency improvements we mean to perform more of a function with the same or less energy or material input.

Energy Efficiency Measures

Energy efficiency measures are those improvement opportunities which exist in a system which when taken will achieve the goals of achieving greater performance.  For example refer to Table 1 of Energy Efficiency Measures which can be effectively reduce energy consumption and provide an ROI of 5 or less years when applied to the commercial refrigeration industry.

energy efficient refrigeration4.jpg

Table 1:  Commercial Refrigeration Energy Efficiency Measures (3)


Government Action on Energy Efficiency

Energy efficiency has been put forward as one of the most effective methods in efforts to address the issue of Climate Change.  Recently, on February 19, 2015, President Obama signed Executive Order (EO) 13693.

“Since the Federal Government is the single largest consumer of energy in the Nation, Federal emissions reductions will have broad impacts.  The goals of EO 13693 build on the strong progress made by Federal agencies during the first six years of the Administration under President Obama’s 2009 Executive Order on Federal Leadership on Environmental, Energy and Economic Performance, including reducing Federal GHG emissions by 17 percent — which helped Federal agencies avoid $1.8 billion in cumulative energy costs — and increasing the share of renewable energy consumption to 9 percent.  

With a footprint that includes 360,000 buildings, 650,000 fleet vehicles, and $445 billion spent annually on goods and services, the Federal Government’s actions to reduce pollution, support renewable energy, and operate more efficiently can make a significant impact on national emissions. This EO builds on the Federal Government’s significant progress in reducing emissions to drive further sustainability actions through the next decade. In addition to cutting emissions and increasing the use of renewable energy, the Executive Order outlines a number of additional measures to make the Federal Government’s operations more sustainable, efficient and energy-secure while saving taxpayer dollars. Specifically, the Executive Order directs Federal agencies to:

– Ensure 25 percent of their total energy (electric and thermal) consumption is from clean energy sources by 2025.

– Reduce energy use in Federal buildings by 2.5 percent per year between 2015 and 2025.

– Reduce per-mile GHG emissions from Federal fleets by 30 percent from 2014 levels by 2025, and increase the percentage of zero emission and plug in hybrid vehicles in Federal fleets.

– Reduce water intensity in Federal buildings by 2 percent per year through 2025. ” (4)


Summary

Energy efficiency has gained recognition as a leading method to reduce the emissions of GHG’s seen to be the cause of climate change.  Under scrutiny, we find that there are different measures of efficiency across different industry, fuel types and levels.  For example on a micro-level, the functioning of a system may be improved by including higher efficiency components in it’s design, such as motors and pumps.

However, there are other changes which can improve efficiency.  Adding automated computer controls can improve a system level efficiency.   Utilities may change from coal burning to natural gas fired power plants, or industry may convert to a process to include for co-generation.  Battery storage and other technological improvements may come along to fill in the gap.

Historically Energy Efficiency measures have proven to be gaining ground by employing people with the savings earned when applying measures to reduce consumption.  These savings reverberate through the economy in a meaningful way, by reducing the need for the construction of more power plants as one example as we on an individual level.  We consume less energy, and using higher efficiency electronic equipment, and other energy savings measures at a consumer level, our communities are capable of more growth with existing energy supplies.

jEnergy production and consumption, as well as population growths also arise to other issues related to energy consumption, such as water consumption, water waste, and solid material waste.  Building with sustainable materials which promote healthy living environments is gaining importance as we understand the health impacts of a building’s environment on the health and well-being of the occupants.  Energy efficiency in the modern era, as we see from recent government mandates and sustainability programs, such as LEED’s for one, also includes for reductions in water intensity and incorporation of renewable energy programs as an alternative to increasing demand on existing utilities.

 

 

Related Blog Posts:

References

  1. http://www.greentechmedia.com/articles/read/report-u.s.-energy-efficiency-is-a-bigger-industry-than-energy-supply
  2. http://www.eia.gov/emeu/efficiency/measure_discussion.htm
  3. http://www.nwfpa.org/nwfpa.info/component/content/article/52-refrigeration/284-energy-efficient-refrigeration-systems
  4. https://www.whitehouse.gov/administration/eop/ceq/sustainability
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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

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PV Panel Energy Conversion Efficiency Rankings

The purpose of this brief is to investigate into the types of solar panel systems with a look at their theoretical maximum Energy Conversion Efficiency both in research and the top 20 manufactured commercial PV panels. 

PVeff(rev160420)

Figure 1:  Reported timeline of solar cell energy conversion efficiencies since 1976 (National Renewable Energy Laboratory) (1)

Solar panel efficiency refers to the capacity of the panel to convert sunlight into electricity.   “Energy conversion efficiency is measured by dividing the electrical output by the incident light power.” (1)  There is a theoretical limit to the efficiency of a solar cell of “86.8% of the amount of in-coming radiation. When the in-coming radiation comes only from an area of the sky the size of the sun, the efficiency limit drops to 68.7%.”

Figure 1 shows that there has been considerable laboratory research and data available on the various configurations of photo-voltaic solar cells and their energy conversion efficiency from 1976 to date.  One major advantage is that as PV module efficiency increases the amount of material  or area required (system size) to maintain a specific nominal output of electricity will generally decrease.

Of course, not all types of systems and technologies are economically feasible at this time for mainstream production.  The top 20 PV solar cells are listed in Figure 2 below with their accompanying measured energy efficiency.

top-20-most-efficient-solar-panels-chart

Figure 2:  Table of the top 20 most efficient solar panels on the North American Market (2)

Why Monocrystalline Si Panels are more Efficient:

Current technology has the most efficient solar PV modules composed of monocrystalline silicon.  Lower efficiency panels are composed of polycrystalline silicon and are generally about 13 to 16% efficient.  This lower efficiency is attributed to higher occurrences of defects in the crystal lattice which affects movement of electrons.  These defects can be imperfections and impurities, as well as a result of the number of grain boundaries present in the lattice.  A monocrystal by definition has only grain boundaries at the edge of the lattice.  However a polycrystalline PV module is full of grain boundaries which present additional discontinuities in the crystalline lattice; impeding electron flow thus reducing conversion efficiency. (3) (4)

Other Factors that can affect Solar Panel Conversion Efficiency in Installations (5):

Direction and angle of your roof 
Your roof will usually need to be South, East or West facing and angled between 10 and 60 degrees to work at its peak efficiency.

Shade
The less shade the better. Your solar panels will have a lower efficiency if they are in the shade for significant periods during the day.

Temperature
Solar panel systems need to be installed a few inches above the roof in order to allow enough airflow to cool them down.  Cooler northern climates also improve efficiency to partially compensate for lower intensity.

Time of year
Solar panels work well all year round but will produce more energy during summer months when the sun is out for longer.  In the far northern regions the sun can be out during the summer for most of the day, conversely during the winter the sun may only be out for a few hours each day.

Size of system
Typical residential solar panel systems range from 2kW to 4kW. The bigger the system the more power you will be able to produce.  For commercial and larger systems refer to a qualified consultant.

 

References:

  1. https://en.wikipedia.org/wiki/Solar_cell_efficiency
  2. http://sroeco.com/solar/top-20-efficient-solar-panels-on-the-market/
  3. http://energyinformative.org/best-solar-panel-monocrystalline-polycrystalline-thin-film/
  4. http://www.nrel.gov/docs/fy11osti/50650.pdf
  5. http://www.theecoexperts.co.uk/which-solar-panels-are-most-efficient

Solar Energy on Reservoirs, Brownfields and Landfills

One of the downsides to large-scale solar power is finding space suitable for the installation of a large area of PV panels or mirrors for CSP.  These are long-term installations, and will have impact on the land and it’s uses.  There are potential objections to committing areas of undeveloped or pristine land to solar power. 

Solar Energy on Reservoirs:

Floating arrays have been installed on surfaces such as water reservoirs as these “land areas” are already committed to a long-term purpose.  Solar power is considered a good synchronistic fit, and most recently work was completed in England seeing “23,000 solar panels on the Queen Elizabeth II reservoir at Walton-on-Thames”.   (1)

Water utilities are the first to see the benefit of solar panel installations as the power generated is generally consumed by the utilities operations for  water treatment and pumping.  This of course offsets demand requirements from the electrical utility and reduces operating costs with a ROI from the installation.  Possible government or other industry incentives and subsidies may enhance benefits.  Last year a 12,000 panel system was installed on a reservoir near Manchester (UK) and was the second of it’s kind in Britain, dwarfing the original installation of 800 panels.  (2)  (3)

Solar Array on Reservoir Japan MjcxMzAwOQ

Image #1:  World’s largest floating array of PV Solar Panels in Japan (4)

Currently Japan has the most aggressive expansion plans for reservoir installations, with the most recent being the world’s largest of it’s kind.  Recent changes in energy policies and the ongoing problems associated with Nuclear Power has propelled Japan into aggressively seeking alternative forms of energy.

The 13.7-megawatt power station, being built for Chiba Prefecture’s Public Enterprise Agency, is located on the Yamakura Dam reservoir, 75 kilometers east of the capital. It will consist of some 51,000 Kyocera solar modules covering an area of 180,000 square meters, and will generate an estimated 16,170 megawatt-hours annually. That is “enough electricity to power approximately 4,970 typical households,” says Kyocera. That capacity is sufficient to offset 8,170 tons of carbon dioxide emissions a year, the amount put into the atmosphere by consuming 19,000 barrels of oil.” 

“[…]“Due to the rapid implementation of solar power in Japan, securing tracts of land suitable for utility-scale solar power plants is becoming difficult,” Toshihide Koyano, executive officer and general manager of Kyocera’s solar energy group told IEEE Spectrum. “On the other hand, because there are many reservoirs for agricultural use and flood-control, we believe there’s great potential for floating solar-power generation business.”

He added that Kyocera is currently working on developing at least 10 more projects and is also considering installing floating installations overseas.” (4)

Solar Energy on Brownfields:

A Brownfield is defined generally by the EPA  (5)

A brownfield is a property, the expansion, redevelopment, or reuse of which may be complicated by the presence or potential presence of a hazardous substance, pollutant, or contaminant. It is estimated that there are more than 450,000 brownfields in the U.S. Cleaning up and reinvesting in these properties increases local tax bases, facilitates job growth, utilizes existing infrastructure, takes development pressures off of undeveloped, open land, and both improves and protects the environment.

Solar Brownfield 1 D6A13-0092.jpg

Image #2:  6-MW solar PV array on the site of the former Palmer Metropolitan Airfield (6)

Traditionally most solar projects have been built on “Greenfields”, however, on further analysis it makes far more sense to install solar on “Brownfields”.

The U.S. is home to more than 450,000 brownfields – unused property that poses potential environmental hazards. Eyesores as well as potential health and safety threats, brownfield sites reduce urban property values. Rehabilitating them pays off, and in more ways than one, according to a July, 2014 National Bureau of Economic Research (NBER) working paper entitled, ¨The Value of Brownfield Remediation.¨ […]

NBER researchers determined that remediation increased the value of individual brownfield sites $3,917,192, with a median value of $2,117,982. That compares to an estimated per-site cost of $602,000. In percentage terms across the study’s nationally representative sample, EPA-supported clean-ups resulted in property price increases of between 4.9% and 32.2%. (6)

In another example where a Brownfield remediation effort has payed off utilizing a Solar Power upgrade is at the Philadelphia Navy Yard according to a June 2011 report by Dave Levitan (7) where it says:

“The Navy Yard solar array is just one of a growing number of projects across the U.S. that fall into the small category of energy ideas that appear to have little to no downside: turning brownfields — or sites contaminated

Every solar project that rises from an industrial wasteland is one that won’t be built on pristine land.

or disturbed by previous industrial activity — into green energy facilities. Among the successfully completed brown-to-green projects are a wind farm at the former Bethlehem Steel Mill in Lackawanna, New York; a concentrating solar photovoltaic array on the tailings pile of a former molybdenum mine in Questa, New Mexico; solar panels powering the cleanup systems at the Lawrence Livermore National Laboratory’s Superfund site in northern California; and the U.S. Army’s largest solar array atop a former landfill in Fort Carson, Colorado.”

Solar Energy on Landfills:

Building solar power projects on top of closed off landfills appears to be a good idea, however, there are additional considerations and requirements which must be met which would exceed those of a normal type of undisturbed geology.

Construction and ongoing operation of the plant must never break, erode or otherwise impair the functioning integrity of the landfill final closure system (including any methane gas management system) already in place.”  (8) […]

A-Simple-Guide-to-Building-Photovoltaic-Projects-on-Landfills-and-Other-...-copy-3-291x300

Image #3:  Prescriptive Landfill Capping System

In general, the features of a conventional “Subtitle D” final protection barrier cover system on USA waste sites are shown in the illustration above and include the following layers added on top of a waste pile:

  1. First, a foundation Layer – usually soil—covers the trash to fill and grade the area and protect the liner.
  2. Then typically a geomembrane liner or a compacted clay layer .is spread over the site to entomb the waste mass in a water impermeable enclosure.
  3. A drainage layer (i.e. highly transmissive sands or gravels or a manufactured “Geonet”) is next added– especially in areas with heavy rainfall and steeper slopes. This is to prevent the sodden top layers of dirt from slipping off the impermeable barrier (a.k.a. a landslide).
  4. Next, typically 18 inches of soil is added as a “protection layer.”
  5. Finally, an “erosion layer” of soil – typically 6 inches of dirt of sufficient quality to support plant growth (grasses, etc., etc.) which the waste industry calls a “vegetative layer.”

Solar-landfill-table-lo-res

Image #4:  Established Solar Energy Projects on Closed Landfills (9)

As of 2013 we can see that there already have been a number of solar installations and that this number is still growing through to the present as more municipalities seek ways to convert their closed landfills into a renewable resource and asset.

Summary of Solar Energy Project Types by Site

A greenfield site is defined as an area of agricultural or forest land, or some other undeveloped site earmarked for commercial development or industrial projects.  This is compared to a brownfield site which is generally unsuitable for commercial development or industrial projects due to the presence of some hazardous substance, pollutant or contaminant.

While a water reservoir is not a contaminated site, it is generally rendered useless for most purposes, however provides an ideal site for locating solar panels as they provide relatively large areas of unobstructed sun.  Also reservoirs provide water cooling which enhances energy efficiency and PV performance.  Uncovered reservoirs can be partially covered by floating arrays of PV panels, of modest to large sizes in the 16 MW range.  Installations can be found throughout the world, including England and most recently Japan where interest in alternative energy sources is growing rapidly.

A brownfield site is considered ideal for the location of a solar plant as a cost-effective method of an otherwise useless body of land, such as a decommissioned mine, quarry, or contaminated site.  A landfill is one form of brownfield site which could be suitable for the installation of solar power where provision has been made to protect the cap on the landfill.  Municipalities have been showing growing interest in landfill solar as a means to offset operational costs.

Abbreviations:

PV – Photo Voltaic

CSP – Concentrated Solar Power

ROI – Return On Investment

UK – United Kingdom

NBER – National Bureau of Economic Research

EPA – Environmental Protection Agency

References:

  1. http://www.theguardian.com/environment/2016/feb/29/worlds-biggest-floating-solar-farm-power-up-outside-london
  2. http://www.telegraph.co.uk/finance/newsbysector/energy/11954334/United-Utilities-floats-3.5m-of-solar-panels-on-reservoir.html
  3. http://www.telegraph.co.uk/news/earth/energy/solarpower/11110547/Britains-first-floating-solar-panel-project-installed.html
  4. http://spectrum.ieee.org/energywise/energy/renewables/japan-building-worlds-largest-floating-solar-power-plant
  5. https://www.epa.gov/brownfields/brownfield-overview-and-definition
  6. http://microgridmedia.com/massachusetts-pv-project-highlights-benefits-of-solar-brownfields/
  7. http://e360.yale.edu/feature/brown_to_green_a_new_use_for_blighted_industrial_sites/2419/
  8. http://solarflexrack.com/a-simple-guide-to-building-photovoltaic-projects-on-landfills-and-other-waste-heaps/
  9. http://www.crra.org/pages/Press_releases/2013/6-3-2013_CRRA_solar_cells_on_Hartford_landfill.htm

Solar Energy and Battery Storage Coupled Provide Demand Response & Utility Peak Shaving

Borrego Solar, a developer, and Stem, an energy storage firm, discuss when PV, storage or both will benefit commercial customers the most.

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

>” […] Thanks to advancements in technology, there are more energy solutions available to consumers. As a result, the confusion about which option to choose — solar, storage or solar-plus-storage — is growing.

Utility energy costs

To understand the benefits of energy storage and solar at a customer facility, it’s essential to first understand the elements of most organizations’ utility energy costs: energy charges and demand charges. This is the bread and butter for energy managers, but many leaders in finance and/or operations aren’t as aware of the energy cost mix — despite it being one of their largest budgetary line items. It should be noted that this billing structure isn’t in place in every market.

Energy charges, the price paid for the amount of energy used over the course of the billing cycle, are how most people think of paying for electricity. A price is paid for every kilowatt-hour used. Demand charges are additional charges incurred by most commercial customers and are determined by the highest amount of energy, in kilowatts, used at any instant or over some designated timeframe — typically a 15-minute interval — in that billing cycle.

Demand charges are a bit more complex. They come from a need for the grid infrastructure to be large enough to accommodate the highest amount of energy, or demand, needed at any moment in order to avoid a blackout. Every region is different, but demand charges typically make up somewhere between 20 percent and 40 percent of an electricity bill for commercial customers.

Why storage?

Intelligent storage can help organizations specifically tackle their demand charges. By combining predictive software and battery-based storage, these systems know when to deploy energy during usage peaks and offset those costly demand charges. Most storage systems run completely independently from solar, so they can be added to a building whether or not solar is present.

Storage can reduce demand charges by dispensing power during brief periods of high demand, which in essence shaves down the peaks, or spikes, in energy usage. Deploying storage is economical under current market conditions for load profiles that have brief spikes in demand, because a relatively small battery can eliminate the short-lived peaks.

For peak demand periods of longer duration, a larger, and considerably more expensive, battery would be needed, and with the higher material costs, the economics may not be cost-effective. As system costs continue to decline, however, a broader range of load profiles will be able to save with energy storage.

Why solar?

For the commercial, industrial or institutional energy user, solar’s value proposition is pretty simple. For most facilities in states with high energy costs and a net metering regime in place, onsite solar can reduce energy charges and provide a hedge against rising electricity costs. The savings come primarily from producing/buying energy from the solar system, which reduces the amount of energy purchased from the utility, and — when the installation produces more than is used — the credit from selling the excess energy to the grid at retail rates.

The demand savings are a relatively small part of the benefit of solar because the timing of solar production and peak demand need to line up in order to cut down demand charges. Solar production is greatest from 9 a.m. to 3 p.m., but the peak period (when demand for energy across the grid is highest) is typically from 12 p.m. to 6 p.m. If demand-charge rates are determined by the highest peak incurred, customers with solar will still fall into higher demand classes from their energy usage later in the day, when solar has less of an impact.

That being said, solar can reduce a significant portion of demand charges if the customer is located within a utility area where solar grants access to new, solar-friendly rate schedules. These rate schedules typically reduce demand charges and increase energy charges, so the portion of the utility bill that solar can impact is larger.  […]”<

See on Scoop.itGreen Energy Technologies & Development

Japan Installs World’s Largest Offshore Wind Turbine at Fukushima

offshore wind turbine was anchored by the Fukushima Offshore Wind Consortium and is located approximately 12 miles off the cost of Fukushima, a region of Ja

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

>” The turbine has been built to withstand 65-foot waves.

The 344-foot 7 MW (megawatt) Offshore Hydraulic Drive Turbine features a rotor diameter of 538 feet and three giant blades, each stretching 262 feet in length. The structure is fastened to the seabed by four 20-ton anchors, and loose chains connect the turbine to the seabed, fortifying it against large waves.

One of the chief engineers of the turbine, Katsunobu Shimizu, told NBC News that “These turbines and anchors are designed to withstand 65-foot waves.” He also explained that “here we can get 32-foot-tall tsunamis. That’s why the chains are deliberately slackened.”

The consortium purposely designed the structures to be able to withstand the fierce and unforgiving weather native to Japan’s waters. In fact, this problematic weather even caused issues during the construction of the turbine. Installations had to be reportedly put on hold on four separate occasions because of typhoons.

The offshore wind turbine is one of three planed for the area.

The Fukushima Offshore Wind Consortium is led by Marubeni Corporation and also involves nine other firms, such as Mitsubishi Heavy Industries, which was the company that supplied the turbine. The $401 million project is funded by Japan’s Ministry of Economy, and was created for the purpose of developing and testing the wind technology for additional commercialization, and to bring new industry to the Fukushima region of Japan that was devastated by the earthquake in 2011.

The 7 MW offshore wind turbine is one of three turbines planned for the facility. When the final turbine is installed later this year, the three turbines are expected to generate a combined total of 14 MW. […]”<

See on Scoop.itGreen Energy Technologies & Development

A New Era for Geothermal Energy in Alberta?

Standard thinking for decades has been that geothermal technology is too costly and inefficient to be a significant source of energy. But a growing number of experts say the time may be right for geothermal to assume a higher profile, especially in ‘perfectly situated’ Alberta.

Sourced through Scoop.it from: www.cbc.ca

>” […] The economics of renewable energy projects are improving as governments begin to introduce carbon taxes and other fees on large carbon-emitting facilities, such as coal power plants.

Geothermal power plants turn hot water into electricity. Companies drill underground for water or steam similar to the process of drilling for oil. The heat is brought to the surface and used to spin turbines. The water is then returned underground.

“I think Alberta is perfectly situated to make the technology work,” said Todd Hirsch, chief economist with ATB Financial. “All the geothermal energy experts say it is all wrong for Alberta. You have to go down so deep to get any heat. Well actually, we have experience drilling through four miles [6.4 km] worth of rock to get at other things that are valuable.”

Hirsch describes geothermal as “a perfectly green, perfectly renewable source of electricity.” He also suggests geothermal could be a boon for the province, where companies have had a knack for developing “marginal resources” such as the oilsands.

“I think geothermal energy might be one that Alberta wants to champion specifically because it doesn’t work here,” said Hirsch. “If we can make it work here in Alberta, then it is a cinch to sell the technology to the Chinese and the Germans and everyone elsewhere geothermal doesn’t work.” […]

What are the costs?

Geothermal power plants cost more money than natural gas facilities. For some perspective, consider the Neal Hot Springs plant in Oregon that was constructed in 2012 for $139 million for 22 megawatts of production.

The Shepard natural gas power plant in Calgary began operating this year with a total cost of $1.4 billion for 800 megawatts of electricity. In this comparison, the geothermal facility costs three times as much per megawatt of power.

Enbridge, a part-owner of the Neal Hot Springs plant, has said the plant saves about 159,000 tonnes per year of carbon dioxide emissions compared to a similar-sized natural gas facility, and about more than 340,000 tonnes per year compared to a coal power plant.

Coal facilities supply nearly 40 per cent of electricity in Alberta.

While the NDP government has yet to announce a specific policy, the party ran on a campaign platform in the recent election pledging to phase out coal.

Premier Rachel Notley has announced an increase to the province’s carbon pricing rules and is expected to announce significant climate change policies this year. Such changes improve the economics of renewable energy projects, such as geothermal.

“It requires a long-term vision to develop,” said Dunn. “How much do we want to invest in the future?” “<

See on Scoop.itGreen Energy Technologies & Development

Geothermal Energy Projects in BC Show Economic Promise

Two potential geothermal energy projects near Pemberton could generate electricity for about seven cents a kilowatt hour — only slightly higher than the 5.8 cents to 6.1 cents a kilowatt hour cost estimate of the Site C dam project.

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

>” […]  There are no geothermal energy projects operating in B.C. but the study estimated the cost per kilowatt hour for the nine sites would range from 6.9 to 7.1 cents for Pebble Creek and Meager Creek near Pemberton to 17.6 cents for Clarke Lake near Fort Nelson.

BC Hydro senior strategic technology specialist Alex Tu said some of the projects appear promising but stressed the cost estimates are still “very uncertain” and carry a lot of risk.

“Even though it says seven cents a kilowatt hour, it’s still a risky proposition,” he said. “All the geothermal in the province is still looked at as very uncertain and very high risk but if you can make the project happen, seven cents is a good price.”

Tu noted BC Hydro invested tens of millions of dollars drilling at the two Pemberton area sites in the 1970s and 1980s but could only produce enough steam for a 20-kilowatt demonstration facility that operated for 18 months.

Geothermal power facilities work by drilling into the earth and redirecting steam or hot water into turbines that convert the energy from the fluid into electricity.

Tu said Hydro has always been open to geothermal power as an alternative energy source but no geothermal projects have ever been submitted to Hydro in any of its calls for power from independent power producers.

Hydro’s standing offer program offers to pay producers $100 a megawatt hour for smaller energy projects of up to 15 megawatts. The two Pemberton area geothermal sites each have estimated capacities of 50 to 100 megawatts.

Borealis GeoPower chief geologist Craig Dunn, whose Calgary-based firm hopes to build two geothermal power plants in B.C. by 2018, said he was excited by the Kerr Wood study, which was commissioned by BC Hydro and Geoscience BC.

“I think it’s a giant step forward in recognizing that geothermal is a viable energy opportunity for the province of British Columbia,” he said.

Dunn said the drilling and turbine technology associated with geothermal power continues to improve, making that form of energy more economically viable than ever.

“As a private developer, I know that my costs are significantly less than the estimates,” he said.

Tu estimated the cost of the two proposed Borealis geothermal sites near Valemount and Terrace at about $120 to $140 a megawatt hour but Dunn said current drilling economics — with many drilling rigs now inactive due to the oil industry slowdown — could cut that estimate by 25 to 50 per cent.  […]”<

See on Scoop.itGreen Energy Technologies & Development

California Resort Hotel First to Upgrade to Energy Storage + EV Charging

Shore Hotel in Santa Monica, California, is a luxury establishment with an energy storage system and fast DC electric vehicle (EV) charging — reportedly, the first one in the US to have this setup. It is expected that the lithium-ion energy storage system will help it reduce electricity demand charges by 50%. Over time, that savings

Source: cleantechnica.com

>” […]  So what is the connection between energy storage and EV charging? When an EV is plugged into a charger, electricity demand increases, so the hotel could be on the hook for a high rate for the electricity, depending on the time of day. Demand charges are based on the highest rate for 15 minutes in a billing cycle. So, obviously, a business would want to avoid spikes in electricity usage so it would not have to pay that rate.

That’s where the energy storage comes in. When there is a spike, electricity can be used from the energy storage system, instead of from a utility’s electricity. Avoiding demand charges in this way, as noted above, can thus help businesses save money. […]”<

See on Scoop.itGreen Energy Technologies & Development

UK Green Investment Bank Raises £463m on its planned £1bn Offshore Wind Farm Fund

The UK Green Investment Bank plc (GIB) has announced that its FCA regulated subsidiary, UK Green Investment Bank Financial Services Limited (GIBFS), has reached first close on commitments of £463m on its planned £1bn fund to invest in operating offshore wind farms in the UK.

Source: www.greeninvestmentbank.com

>” […] £463m of capital raised at first close, to be invested in UK offshore wind projects.Investors include UK pension funds and a sovereign wealth fund.Innovative transaction creating the world’s first dedicated offshore wind fund.This is the first fund raised by the GIB group, a first move into asset management and the first time it has managed private capital since its formation.This announcement marks the end of GIB’s financial year. It committed £723m to 22 green energy projects across the UK in 2014/15. GIB has now backed 46 UK projects with a total value of almost £7bn.

The UK Green Investment Bank plc (GIB) has announced that its FCA regulated subsidiary, UK Green Investment Bank Financial Services Limited (GIBFS), has reached first close on commitments of £463m on its planned £1bn fund to invest in operating offshore wind farms in the UK.

First close marks the completion of the first stage of fundraising and is triggered by the commitment of an initial group of investors.

The initial investors comprise UK-based pension funds and a major sovereign wealth fund. GIB is also investing £200m in the fund. Fundraising continues and GIBFS expects to raise additional funds from other investors to reach the £1bn target.

In addition to the £463m of fund commitments raised, an additional significant amount of investor capital is available to co-invest into projects alongside the fund.

The fund is an innovative, first-of-a-kind transaction. It is the world’s first fund dedicated to investments in offshore wind power generation and, once fully subscribed, will be the largest renewables fund in the UK. The fund has an expected life of 25 years, allowing a new class of long-term investor to enter the sector.

This is the first fund raised by the GIB group and its first step into asset management. It is also the first private capital to be managed by the GIB group. It will be managed by a new FCA-regulated and authorised subsidiary called UK Green Investment Bank Financial Services Limited which is staffed by a dedicated team.

GIB has now transferred its investments in two operating assets into the fund, which will produce immediate cash yield for investors. They include:

Rhyl Flats. A 90 MW, 25 turbine wind farm operated by RWE Innogy UK off the coast of North Wales. It has been operational since December 2009. GIB has sold its full 24.95% equity stake in the project to the Fund.Sheringham Shoal. A 317 MW, 88 turbine wind farm operated by Statkraft and located in the Greater Wash area off the coast of Norfolk. It has been operational since October 2012. GIB has sold its full 20% equity stake in the project to the fund.

These two offshore wind farms are able to produce 1,290 GWh of renewable energy annually, enough to power 305,000 UK homes. The fund also has a strong pipeline of future investment opportunities.

Evercore Private Funds Group is acting as advisor and exclusive global placement agent for the fundraise and King & Wood Mallesons is acting as legal counsel to the fund. […]”<

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