There are many metrics and measurements when it comes to evaluating energy as we use it in our daily lives. In order to compare between different sources or end uses we often have to make conversions in our terms so that our comparisons are equitable. This may be further complicated as different countries often use different standards of measure, however, we will convert to common units.
Benchmarking is the practice of comparing the measured performance of a device, process, facility, or organization to itself, its peers, or established norms, with the goal of informing and motivating performance improvement. When applied to building energy use, benchmarking serves as a mechanism to measure energy performance of a single building over time, relative to other similar buildings, or to modeled simulations of a reference building built to a specific standard (such as an energy code). (1)
Benchmarking is a common practice in buildings to establish existing consumption rates and to identify areas that require improvement and to help prioritize improvement projects. These benchmarks can be established for a building, system within a building, or even a larger campus, facility or power source. Usually an energy or facility manager will determine energy consumption over a fixed period of time, 1 to 3 years, and compare it to similar facilities. Normalized by gross square footage of the building the EUI is usually expressed as kBtu/sf per year.
Energy Intensity (EI) of a Country
Figure 1: Energy Intensity of different economies The graph shows the amount of energy it takes to produce a US $ of GNP for selected countries. (2)
Not to be confused with Energy Use Intensity, Energy Intensity is an economic measure of energy use normalized by the GDP of a country and is considered a measure of a Nation’s Energy Efficiency. Countries with a high EI have a higher cost to convert energy into GDP, whereas countries with low EI have lower costs of converting energy into GDP. Many factors contribute to the EI value, including climate, energy sources and economic productivity. (2)
Energy Use Intensity (EUI)
The EUI of a building includes the electrical power use and heating fuel consumption for heating and hot water generation. Many facilities require different loads according to their primary use or function, including cooling and refrigeration. For the comfort of occupants electricity is needed for lighting and plug loads to meet the functioning needs of the equipment in the facility. Heating, ventilation and air conditioning (HVAC) may require electricity or another fuel such as natural gas. Hot water may be generated with electricity or a fuel. A site may also have solar PV or hot water, wind power, and daylighting programs. There are also many strategies which may be employed by building operators to reduce loads and energy consumption including controls, storage, micro-grid, purchasing offsets, etc.
When comparing buildings, people not only talk about total energy demands, but also talk about “energy use intensity” (EUI). Energy intensiveness is simply energy demand per unit area of the building’s floorplan, usually in square meters or square feet. This allows you to compare the energy demand of buildings that are different sizes, so you can see which performs better.
EUI is a particularly useful metric for setting energy use benchmarks and goals. The EUI usually varies quite a bit based on the building program, the climate, and the building size. (3)
Figure 2. Typical EUI for selected buildings. This graph is based on research EPA conducted on more than 100,000 buildings (4)
Site Energy vs Source Energy
As we go forward into the future, it is rather unclear how current events will affect the international agreements on reducing carbon consumption. However, generally speaking, renewable energy sources are seen to becoming more economic for power production. For many facilities this means that supplementing existing grid sources for power with on-site power production is making economic sense. Future building improvements may include sub-systems, batteries and energy storage schemes, renewable sources or automated or advanced control systems to reduce reliance on grid sourced power.
The energy intensity values in the tables above only consider the amount of electricity and fuel that are used on-site (“secondary” or “site” energy). They do not consider the fuel consumed to generate that heat or electricity. Many building codes and some tabulations of EUI attempt to capture the total impact of delivering energy to a building by defining the term “primary” or “source” energy which includes the fuel used to generate power on-site or at a power plant far away.
When measuring energy used to provide thermal or visual comfort, site energy is the most useful measurement. But when measuring total energy usage to determine environmental impacts, the source energy is the more accurate measurement.
Sometimes low on-site energy use actually causes more energy use upstream. For example, 2 kWh of natural gas burned on-site for heat might seem worse than 1 kWh of electricity used on-site to provide the same heating with a heat pump. However, 1 kWh of site electricity from the average US electrical grid is equal to 3.3 kWh of source energy, because of inefficiencies in power plants that burn fuel for electricity, and because of small losses in transmission lines. So in fact the 2 kWh of natural gas burned on site is better for heating. The table below provides the conversion factors assumed by the US Environmental Protection Agency for converting between site and source energy. (3)
(1) BUILDING ENERGY USE BENCHMARKING https://energy.gov/eere/slsc/building-energy-use-benchmarking
(2) ENERGY INTENSITY https://en.wikipedia.org/wiki/Energy_intensity
(3) MEASURING BUILDING ENERGY USE https://sustainabilityworkshop.autodesk.com/buildings/measuring-building-energy-use
(4) WHAT IS ENERGY USE INTENSITY (EUI)? https://www.energystar.gov/buildings/facility-owners-and-managers/existing-buildings/use-portfolio-manager/understand-metrics/what-energy
As gridlock continues to be a problem in the United States, exacerbated by crumbling infrastructure, the American public has reportedly approved up to $200 billion for rapid and mass transit.
According to the American Public Transportation Association (Apta), the 49 ballot measures totalling nearly $US 200bn that were voted on were the largest in history. […]
The largest measure in the country, Los Angeles County’s Measure M, was passed with 69% approval with all precincts reporting. The sales tax increase needed a two-thirds majority to pass and is expected to raise $US 120bn over 40 years to help fund transport improvement projects, including Los Angeles County Metropolitan Transportation Authority (LACMTA) schemes to connect Los Angeles International Airport to LACMTA’s Green Line, Crenshaw/LAX line and bus services; extend the Purple Line metro to Westwood; extend the Gold Line 11.7km; extend the Crenshaw Line north to West Hollywood; and build a 6.1km downtown light rail line. The measure will also provide $US 29.9bn towards rail and bus operations, and $US 1.9bn for regional rail.
California’s other big transit wins include Measure RR in the San Francisco Bay area, which will authorise $US 3.5bn in bonds for Bay Area Rapid Transit rehabilitation and modernisation. It required a cumulative two-thirds vote in San Francisco, Alameda and Contra Costa counties for passage and received 70% approval. (1)
Figure 1. Bay Area Rapid Transit (2)
BART’s Focus on Material Conservation, Energy Savings and Sustainability
BART’s infrastructure requires the train cars to be extremely lightweight. To meet this requirement, most of the exterior of the new train cars will be constructed out of aluminum. Aluminum is abundant, doesn’t rust, and when properly finished, reflects heat and light, keeping the train cars cool. It is lightweight but strong, yet fairly easy to work with, reducing the energy investment during the manufacturing process. Additionally, aluminum is easily and readily recyclable, making it very low impact when the train cars are eventually retired and dismantled. (2)
Federal Investment in Rapid Transit and Transportation Infrastructure Lagging
Yet, despite the public’s continued desire to see greater investment in transit, historically transit has received only a small minority of funding at the federal level. Currently, only 20 percent of available federal transportation funds are invested in transit and just 1 percent of funds are invested in biking and walking infrastructure. Meanwhile, 80 percent of federal transportation dollars continue to be spent on roads.
“While many localities recognize the need to invest in transit, biking, and pedestrian solutions that can bring our transportation system into the 21st century, federal officials remain woefully behind the curve,” said Olivieri. “While it is great to see such widespread support of transit at the local level, the need for these measures speaks volumes about how out of sync federal decision makers are with the wants and needs of the American people,” he added.
The nation currently faces an $86 billion transit maintenance repair backlog, while data from the Federal Highway Administration’s National Bridge Inventory show that despite the large discrepancy at the federal level between investment in transit and spending on roads, the nation’s road system is in similarly bad shape. To date, more than 58,000 bridges remain structurally deficient.
“Despite the fact that roads receive 80 percent of available federal transportation dollars, both transit and roads continue to face enormous repair and maintenance backlogs,” said Lauren Aragon, Transportation Fellow at U.S. PIRG. “While the overall level of funding is important, how states spend the limited federal funding they receive can have even greater consequences but states continue to funnel road funding into new and wider highway projects, leaving the existing system to crumble. We need to fix what we have already built first,” she added. (3)
Figure 2. Typical image of steel bridge in disrepair (4)
Harvard Business Review Reports on Crumbling American Infrastructure
Bridges are crumbling, buses are past their prime, roads badly need repair, airports look shabby, trains can’t reach high speeds, and traffic congestion plagues every city. How could an advanced country, once the model for the world’s most modern transportation innovations, slip so badly?
The glory years were decades ago. Since then, other countries surpassed the U.S. in ease of getting around, which has implications for businesses and quality of life. For example, Japan just celebrated the 50thanniversary of its famed bullet train network, the Shinkansen. Those trains routinely operate at speeds of 150 to 200 miles per hour, and in 2012, the average deviation from schedule was a miniscule 36 seconds. Fifty years later, the U.S. doesn’t have anything like that. Amtrak’s “high-speed” Acela between Washington, D.C., and Boston can get up to full speed of 150 mph only for a short stretch in Rhode Island and Massachusetts, because it is plagued by curves in tracks laid over a century ago and aging components, such as some electric overhead wiring dating to the early 1900s.
Numerous problems plague businesses and consumers: Goods are delayed at clogged ports. Delayed or cancelled flights cost the U.S. economy an estimated $30-40 billion per year – not to mention ill will of disgruntled passengers. The average American wastes 38 hours a year stuck in traffic. This amounts to 5.5 billion hours in lost U.S. productivity annually, 2.9 gallons of wasted fuel, and a public health cost of pollution of about $15 billion per year, according to Harvard School of Public Health researchers. The average family of four spends as much as 19% of its household budget on transportation. But inequality also kicks in: the poor can’t afford cars, yet are concentrated in places without access to public transportation. To top it all, federal funding for highways, with a portion for mass transit, is about to run out. (4)
(1) Nearly 70% of US transit ballot measures pass; http://www.railjournal.com/index.php/north-america/nearly-70-of-us-transit-ballot-measures-pass.html
(2) BART – New Train Car Project; http://www.bart.gov/about/projects/cars/sustainability
(3) BILLIONS IN TRANSIT BALLOT INITIATIVES GET GREEN LIGHT; http://www.uspirg.org/news/usp/billions-transit-ballot-initiatives-get-green-light
(4) What It Will Take to Fix America’s Crumbling Infrastructure; https://hbr.org/2015/05/what-it-will-take-to-fix-americas-crumbling-infrastructure
The future for the metal aluminum has never looked better, for the great investment it represents as a multi-faceted energy efficiency lending material, electrical energy storage medium (battery), and for the advancement of renewable energy sources. These are spectacular claims, and yet in 1855 aluminum was so scarce it sold for about 1200 $/Kg (1) until metallurgists Hall & Heroult invented the modern smelting process over 100 years ago (2).
Figure 1. Schematic of Hall Heroult Aluminum Reduction Cell (3)
Aluminum is an energy intensive production process. High temperatures are required to melt aluminum to the molten state. Carbon electrodes are used to melt an alchemical mixture of alumina with molten cryolite, a naturally occurring mineral. The cryolite acts as an electrolyte to the carbon anode and cathodes. Alumina (Al2O3) also known as aluminum oxide or Bauxite is fed into the cell and dissolved into the cryolite, over-voltages reduce the Al2O3 into molten aluminum which pools at the bottom of the cell and is tapped out for further refining.
Aluminum Smelting Process as a Battery
The smelting of Aluminum is a reversible electrolytic reaction, and with modifications to current plant design it is possible to convert the process to provide energy storage which can be tapped and supplied to the electrical grid when required. According to the research the biggest challenge to this conversion process is to maintain heat balances of the pots when discharging energy to prevent freeze-up of the cells. Trimet Aluminum has overcome this problem by incorporating shell heat-exchange technology to the sides of the cell to maintain operating temperatures. Trial runs with this technology have been positive where plans are to push the technology to +/- 25% energy input/output. If this technology is applied to all 3 Trimet plants in Germany, it is claimed that up to 7700 MWh of electrical storage is possible (4).
Trimet Aluminum SE, Germany’s largest producer of the metal, is experimenting with using vast pools of molten aluminum as virtual batteries. The company is turning aluminum oxide into aluminum by way of electrolysis in a chemical process that uses an electric current to separate the aluminum from oxygen. The negative and positive electrodes, in combination with the liquid metal that settles at the bottom of the tank and the oxygen above, form an enormous battery.
By controlling the rate of electrolysis, Trimet has been able to experiment with both electricity consumption and storage. By slowing down the electrolysis process, the plant is able to adjust its energy consumption up and down by roughly 25 percent. This allows the plant to store power from the grid when energy is cheap and abundant and resell power when demand is high and supply is scarce. (5)
Figure 2. TRIMET Aluminium SE Hamburg with emission control technology (6)
Figure 3. Rio Tinto Alcan inaugurates new AP60 aluminum smelter in Quebec (7)
Aluminum as a Material and it’s Energy Efficiency Properties
Aluminum and it’s alloys generally have high strength-to-weight ratio’s and are often specified in the aircraft industry where weight reduction is critical. A plane made of steel would require more energy to fly, as the metal is heavier for a given strength. For marine vessels, an aluminum hull structure, built to the same standards, weighs roughly 35% to 45% less than the same hull in steel (8). Weight reduction directly converts to energy savings as more energy would be required to propel the aircraft.
Other modes of transportation, including automobiles, trucking, and rail transport may similarly also benefit from being constructed of lighter materials, such as aluminum. Indeed this would continue the long-standing trend of weight reduction in the design of vehicles. The recent emergence of electric vehicles (EV’s) have required weight reduction to offset the high weight of batteries which are necessary for their operations. The weight reduction translates into longer range and better handling.
Figure 4. Tesla Model S (9)
In the 1960s, aluminium was used in the niche market for cog railways. Then, in the 1980s, aluminium emerged as the metal of choice for suburban transportation and high-speed trains, which benefited from lower running costs and improved acceleration. In 1996, the TGV Duplex train was introduced, combining the concept of high speed with that of optimal capacity, transporting 40% more passengers while weighing 12% less than the single deck version, all thanks to its aluminium structure.
Today, aluminium metros and trams operate in many countries. Canada’s LRC, France’s TGV Duplex trains and Japan’s Hikari Rail Star, the newest version of the Shinkansen Bullet train, all utilize large amounts of aluminium. (10)
Figure 5. Image of Japanese Bullet Train (11)
Aluminum For Renewable Energy
One of the biggest criticisms against renewable technologies, such as solar and wind has been that they are intermittent, and not always available when demand demand for energy is high. Even in traditional grid type fossil fuel plants it has been necessary to operate “peaker plants” which provide energy during peak times and seasons.
In California, recent technological breakthroughs in battery technology have been seen as a means of providing storage options to replace power plants for peak operation. However, there remains skepticism that battery solutions will be able to provide the necessary storage capacity needed during these times (12). The aluminum smelter as an energy provider during these high demand times may be the optimum solution needed in a new age renewables economy.
The EnPot technology has the potential to make the aluminium smelting industry not only more competitive, but also more responsive to the wider community and environment around it, especially as nations try to increase the percentage of power generated from renewable sources.
The flexibility EnPot offers smelter operators can allow the aluminium industry to be part of the solution of accommodating increased intermittency. (13)
(4) The ‘Virtual Battery‘ – Operating an Aluminium Smelter with Flexible Energy Input. https://energiapotior.squarespace.com/s/Enpot-Trimet-LightMetals2016.pdf
Figure 1: Radial Outflow Turbine Generator – Organic Rankine Cycle – ORC Turbine (1)
Existing oil and gas wells offer access to untapped sources of heat which can be converted to electricity or used for other energy intensive purposes. This includes many abandoned wells, which can be reactivated as power sources. These wells, in many cases “stranded assets” have been drilled, explored, and have roads built for access. This makes re-utilization of existing infrastructure cost-effective while minimizing harm to the environment associated with exploration.
In a recently published article in Alberta Oil, an oil & gas industry magazine they point out many of the benefits of converting existing and abandoned wells to geothermal energy.
A recent Continental Resources-University of North Dakota project in the Williston Basin is producing 250 kW of power from two water source wells. The units fit into two shipping containers, and costs US$250,000. This type of micro-generation is prospective in Alberta, and a handful of areas also have potential for multi-MW baseload power production.
In addition to producing power, we can use heat for farming, greenhouses, pasteurization, vegetable drying, brewing and curing engineered hardwood. Imagine what Alberta’s famously innovative farmers and landowners would accomplish if they were given the option to use heat produced from old wells on their properties. Northern communities, where a great many oil and gas wells are drilled nearby, can perhaps reap the most benefits of all. Geothermal can reduce reliance on diesel fuel, and provide food security via wellhead-sourced, geothermally heated, local greenhouse produce. (2)
Water can be recirculated by pumps to extract heat from the earth, and through heat exchangers be used as a source of energy for various forms of machines designed to convert low grade waste heat into electricity. The Stirling Cycle engine is one such mechanical device which can be operated with low grade heat. However recent developments in the Organic Rankine Cycle (ORC) engine seem to hold the greatest promise for conversion of heat to electricity in these installations.
In a “boom or bust” industry subject to the cycles of supply and demand coupling a new source of renewable energy to resource extraction makes sense on many fronts. It could be an economic stimulus not only to the province of Alberta, but throughout the world where oil and gas infrastructure exists, offering new jobs and alternative local power sources readily available.
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Much of our efforts to reduce carbon emissions involves fairly complicated and advanced technologies. Whether it’s solar panels, batteries, flywheels, or fuel cells, these technologies have typically required public support to bring them to scale at a reasonable price, along with significant regulatory or legal reforms to accommodate these new ways of doing old things, […]
To recommend policies to boost this capital market financing for energy retrofits, UC Berkeley and UCLA Law are today releasing a new report “Powering the Savings:How California Can Tap the Energy Efficiency Potential in Existing Commercial Buildings.” The report is the 17th in the two law schools’ Climate Change and Business Research Initiative, generously supported by Bank of America since 2009.
The report describes ways that California could unlock more private investment in energy efficiency retrofits, particularly in commercial buildings. This financing will flow if there’s a predictable, long-term, measured and verified amount of savings that can be directly traced to energy efficiency measures. New software and methodologies can now more accurately perform this task. They establish a building’s energy performance baseline, calibrating for a variety of factors, such as weather, building use, and occupancy changes. That calibrated or “dynamic” baseline can then form the basis for calculating the energy savings that occur due specifically to efficiency improvements.
But the state currently lacks a uniform, state-sanctioned methodology and technology standard, so utilities are reluctant to base efficiency incentives or programs without regulatory approval to use these new methods. The report therefore recommends that energy regulators encourage utilities to develop aggressive projects based on these emerging metering technologies that can ultimately inform a standard measurement process and catalyze “pay-for-performance” energy efficiency financing, with utilities able to procure energy efficiency savings just like they were a traditional generation resource. […]
In the beginning, the Master Economist created the Economy. He created businesses large and small, consumers, governments with their regulation, and financial institutions of all types. And the Ma…
Source: How Energy Shapes the Economy
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.
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.
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)
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.
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“Apple has created a subsidiary to sell the excess electricity generated by its hundreds of megawatts of solar projects. The company, called Apple Energy LLC, filed a request with the Federal Energy Regulatory Commission to sell power on wholesale markets across the US.
The company has announced plans for 521 megawatts of solar projects globally. It’s using that clean energy to power all of its data centers, as well as most of its Apple Stores and corporate offices. In addition, it has other investments in hydroelectric, biogas, and geothermal power, and looks to purchase green energy off the grid when it can’t generate its own power. In all, Apple says it generates enough electricity to cover 93 percent of its energy usage worldwide.
But it’s possible that Apple is building power generation capacity that exceeds its needs in anticipation of future growth. In the meantime, selling off the excess helps recoup costs by selling to power companies at wholesale rates, which then gets sold onward to end customers.
It’s unlikely that Apple, which generated more than $233 billion in revenue in fiscal 2015, will turn power generation into a meaningful revenue stream — but it might as well get something out of the investment. The company issued $1.5 billion in green bonds earlier this year to finance its clean energy projects.” (2)