Geothermal energy systems rely on two basic components: the heat beneath the earth’s crust, and the subterranean waters that the earth’s heat will turn to steam. In most geothermal systems, accessing these components involves drilling as deep as two miles below the surface of the earth.
In direct-use geothermal systems, the earth’s natural steam is piped directly into buildings to warm them in winter and, perhaps surprisingly, to cool them in summer. While the temperature on the surface of the earth varies throughout the year, the temperature in the upper ten feet of the earth remains fairly constant, usually between 50 and 60 degrees F. The benefits of this constant temperature can be accessed by pumping the water from springs or reservoirs near the earth’s surface into buildings for interior climate control.
Direct-use of geothermal heat is often achieved through the use of a heat pump, which efficiently extracts the earth’s thermal energy. Besides maintaining indoor temperatures, geothermal heat can be used to heat greenhouses, heat water at fish farms, pasteurize milk, and provide the heat required for range of industrial processes. A large centralized geothermal pump can even provide heating for an entire community, known as “district heating.”
Geothermal energy is also used to drive electric generators in a number of ways:
Dry steam systems are the oldest and simplest application of geothermal power, in which the steam released from a geothermal reservoir is captured and used to rotate turbines which generate electricity.
Flash steam systems utilize a more technologically sophisticated method of electrical generation and are the most widely deployed. These systems use intense pressure to keep water in liquid form, even as it is heated to temperatures well above its boiling point at sea level. The water is then exposed to an abrupt drop in pressure, causing it to convert in a flash to steam, which more efficiently rotates the steam turbines to generate electricity.
Binary cycle systems direct the earth’s hot water upward to a heat exchanger above ground, where the heat is transferred to a pipe containing a fluid with a much lower boiling point than water (usually isobutane or isopentane gas). The transferred heat vaporizes the liquid, and that steam rotates turbines to produce electricity. The advantage of this system is that it can make use of geothermal reservoirs that have lower temperatures, increasing the places where geothermal systems can be located.
Enhanced geothermal systems (EGS) (or hot dry rock systems) may be yet another avenue into the earth’s deep power potential. Rather than harvesting the heated water already in the earth, this method involves manufacturing steam by piping surface water down into the hot but dry rocks in the earth’s crust. A main benefit of this system is that it does not require the high temperature geothermal resources of other geothermal electric technologies, and it can be used nearly anywhere on the planet. While the technology’s potential is great, further research and development is required before it can be deployed at scale.
To learn more about geothermal systems, visit U.S. Department of Energy’s geothermal overview.
- The U.S. has approximately 3,200 megawatts (MW) of installed geothermal capacity, accounting for about 28% of global capacity. (Geothermal Energy Association (GEA))
- As of April 2012, there were 147 projects identified under development in the U.S. (130 of which are confirmed by developing companies), with roughly 5,000 MW of power potential. (GEA)
- In 2011 and early 2012, five additional geothermal plants came online, with a gross capacity of approximately 91 MW. (GEA)
Biomass refers a wide range of biological materials used as sources of energy. While wood products are the most common form of biomass power, a host of feedstocks can be used for electricity generation, including a variety of crops, agricultural waste, yard clippings, and even municipal solid waste (MSW). In addition to producing electricity, biomass can also be used for space and domestic water heating, process heat, and the thermal portion of combined heat and power, as well as for transportation (see Biofuels).
A variety of processes convert biomass materials into electricity:
Incineration/Direct-Firing is the most common method of generation. The biomass feedstocks are burned directly to produce steam, which in turn rotates turbines to generate electricity.
Gasification refers to heating biomass while restricting the amount of oxygen and/or steam in the gasifier. This process produces a synthetic gas known as “syngas,” containing carbon monoxide and hydrogen. The syngas can be burned in gas engines, used to produce methanol and hydrogen, or transformed into a synthetic fuel via the Fischer Tropsch (FT) process.
Co-Firing is the burning of biomass in conjunction with a non-renewable feedstock (often coal) to reduce emissions and, in certain cases, increase output and efficiency. Nitrogen, sulfur oxides, and carbon dioxide emissions are considerably lessened by a biomass co-firing arrangement.
Anaerobic Digestion is a biological process in which microorganisms break down biomass and release biogas, which consists of methane, carbon dioxide, and certain other gasses. The biogas can be subsequently captured and combusted to generate electricity. Anaerobic digestion is used in a variety of locations as a way to manage waste, including at dairy farms, landfills, and wastewater and sewage treatment facilities.
Landfill gas is produced as a result of anaerobic digestion at landfills. Landfill operators collect the gas produced by the decomposition of solid waste and use it to generate electricity.
Pyrolysis is the process of heating biomass in the absence of oxygen. The result of the process is a substance known as pyrolysis oil, which then can be converted into biofuel or used to generate electricity.
- Wood and waste biomass power together are projected to account for roughly 30% of the renewable energy produced in the United States in 2012. (Energy Information Administration (EIA))
- At a projected 6% annual growth rate, biomass is expected to be among the fastest growing renewable energy sources. (EIA)
- Biomass power capacity is forecast to reach to reach 20.2 GW by 2035. (EIA)
Biofuels are transportation fuels made from organic materials. These fuels are usually blended with petroleum, but they can also be used in their pure form. Ethanol and biodiesel are the leading forms of biofuel, and, compared to the fossil fuels they replace, are cleaner-burning and produce fewer air pollutants or carbon emissions.
Ethanol is an alcohol fuel made from the sugars found in a wide range of feedstocks. Most of the ethanol used today is distilled from starch and sugar based feedstocks, including corn, sugarcane, and potatoes. Three commercial plants are opening in 2014 to produce cellulosic ethanol, which is made from the fibrous or cellulosic material in plants.
Nearly all gasoline sold now in the U.S. contains some ethanol. About 99% of the fuel ethanol consumed in the U.S. is added to gasoline in mixtures of up to 10% ethanol and 90% gasoline. Any gasoline powered engine in the U.S. can use E-10 (gasoline with 10% ethanol), but only specific types of vehicles can use mixtures with greater than 10% ethanol. The U.S. Environmental Protection Agency (EPA) ruled in October 2010 that cars and light trucks of model year 2007 and after are capable of running on a 15% ethanol blend. Some other vehicles can utilize even higher blends.
Biodiesel is a fuel made from vegetable oils, fats, greases, and advanced feedstocks like algae, and it can be used in any standard diesel engine. Fuel grade biodiesel is produced to strict industry specifications and is safe, biodegradable, and produces lower levels of most air pollutants than petroleum-based fuels. Most of the biodiesel used in the United States is made from soybean oil, as well as from waste animal fat and grease.
Advanced biofuels (like cellulosic ethanol and algae-based biodiesel) are generally derived from non-edible feedstocks such as forestry and agricultural residues, perennial grasses, algae, and other “energy crops” as well as municipal solid waste. In addition to the benefit of relying on non-food sources for their generation, these biofuels produce much higher energy yields. Conventional biofuels yield 23 – 35% more energy than is used to generate them, while cellulosic biofuels yield 400 – 900% more energy.
- The U.S. is the world leader in ethanol production, responsible for 60% of global output and producing producing 14.3 billion gallons of ethanol in 2014.(RFA)
- Cellulosic ethanol results in 60% fewer greenhouse gas emissions than gasoline (USEPA)
- Airlines, including Virgin Atlantic and British Airways, have been partnering with advanced biofuel companies to develop drop-in aviation biofuel.
- Biodiesel reduces greenhouse gas emissions by at least 57 percent and up to 86 percent when compared to petroleum diesel (NBB)
- Take the ACORE 2013 Member Survey and Be Entered to Win a Pass to REFF-Wall Street
- ABA/ACORE Webinar – Smart Microgrids for Military Installations & Beyond
- US-China Webinar — Fueling the 12th 5 Year Plan: The Outlook on Biofuels in China
- Platts Energy Week TV Features Interview with ACORE President McGinn
- PRESS RELEASE: Public, Private Sector Leaders Chart Renewable Energy Future at ACORE National Renewable Energy Policy Forum
- PRESS RELEASE: ACORE Fully Endorses The Alliance To Save Energy’s Energy Efficiency Policy Recommendations
- Join Us at ACORE’s US-Australian Leadership Roundtables
- New for Members: Sign Up for the Daily Renewable Energy News Email
STORIES FOR PUSHBACK
- Food Costs are Eating American Family Budgets(Farmecon) http://bit.ly/UNf0hs
a) Many opponents of renewable fuel claim that 40% of the nation’s corn crop goes toward ethanol, limiting the supply for other uses. 40% of the nation’s corn crop is purchased by the ethanol industry. However much of that corn, as we can see, is used to produce distillers grains, a high-protein, high value and highly nutritious animal feed. (http://www.ers.usda.gov/media/131100/err114.pdf)
Sample Tweet: The Renewable Fuel Standard lessens our dependence on oil and doesn't increase food prices. Ethanol works for America. http://bit.ly/ZwnqtR
b) Accounting for the production of this important coproduct, only 16% of the nation’s net corn crop actually goes in to making ethanol, a significantly lower number. And globally, only 3% of the grain crop goes toward ethanol. (http://www.growthenergy.org/news-media/press-releases/un-spreading-misinformation-about-biofuels/)
c) According to the United States Department of Agriculture and the Economic Research Service, 84% of food costs are derived from non-farm costs, leaving the cost of food that derives from the farm at 16%. (http://www.growthenergy.org/news-media/ethanol-in-the-news/growth-energy-attempts-to-alter-requests-for-rfs-waiver/)
STORIES FOR AMPLIFICATION
- Former White House aide defends 'green' stimulus, says 720K jobs were created (The Hill) http://bit.ly/WztQWK
Sample tweet: How do you create 720,000 jobs, leverage billions in investment, and reduce carbon emissions? Invest in #cleanenergy. http://bit.ly/10i03Kn
b) Joseph Aldy, a Harvard University economist praises the green stimulus for creating 720,000 jobs. http://bit.ly/10i03Kn
- Google Invests $200 Million in 161-Megawatt Texas Wind Farm (Bloomberg Businessweek) http://buswk.co/TMFBfE Sample Tweet: Google continues to invest in #renewableenergy to reduce energy costs and mitigate carbon footprint. http://buswk.co/VRnsvq
- Wind Tax Credits Breathe New Life Into Our Economy (Huffington Post) http://huff.to/ZrBTan
- Pattern Energy Starts Providing Wind Power for Sempra (Bloomberg) http://bloom.bg/13j0oKG
- Joint base housing to get $35-million solar-panel project (Philly Burbs) http://bit.ly/ZLbxFc
- Solyndra stunk. The green stimulus didn’t. (Washington Post Wonk Blog) http://wapo.st/Ski2fZ
- Guest column: Science proves wind energy is safe for Wisconsin (Green Bay Press Gazette) http://gbpg.net/WDDp6S
STORIES TO WATCH
- Mill officials say renewables not to blame for Maine's high energy costs (Maine Sun Journal) http://bit.ly/VR6s8s
- President Obama’s Clean Energy Progress: How the Top 10 Energy Priorities Fared During His First Term (Center for American Progress) http://bit.ly/XMCVlK
- Chinese Firm Buys U.S. Solar Start-Up (New York Times) http://nyti.ms/VSVsqK
- Maryland Senate President Miller: 'Wind energy will pass' (Washington Business Journal) http://bit.ly/XmP50F
- Obama administration cuts hybrid, electric buys (Detroit Free Press) http://on.freep.com/TMumUu
- A Preliminary Review of the American Recovery and Reinvestment Act’s Clean Energy Package (Resources for the Future) http://bit.ly/RGuB3H
- Interactive Tool For Developing A Cleaner Energy Future (Clean Technica) http://bit.ly/Sm2Qij
- Unleashing Private-Sector Energy R&D (American Energy Innovation Council) http://bit.ly/13i8Jzd
National & State Politics
- Wyden names energy committee staff (The Hill) http://bit.ly/11gMSbY
- Incentives Watch: Fiscal Cliff Legislation Temporarily Bolsters Renewable Energy Industry (Bloomberg BNA) http://bit.ly/11j15VX
- Desert Plan Could Fast Track Green Energy Projects (KPBS News) http://bit.ly/VfoS5R
Solar, Wind, Hydro, Biomass
- Google Keeps Its Renewable Energy Investments Going (The Atlantic) http://bit.ly/VTqyys
- Google puts $200 million in Texas wind farm (San Francisco Chronicle) http://bit.ly/ULVIsQ
- The Promises and Challenges of Wind Power in the US (Huffington Post) http://huff.to/11iGfWw
- Wind Energy: Twisting and Turning and Getting Bent out of Shape (Forbes) http://onforb.es/XNPs8B
- The Wind Technology Testing Center: Pushing the Envelope on Wind Technology (Forbes) http://onforb.es/XN7jN0
- What can the city 'claw back' in solar deal? (San Antonio Express News) http://bit.ly/UXJvCv
- Sempra completes first phase of Arizona solar power plant (Reuters) http://reut.rs/XQVXHD
- Under Construction: The World's Largest Thermal Solar Plant (NPR) http://n.pr/ULm3eo
Vehicles, Biofuels, Electrification
- Renewable Fuels Group Excited About Governor Leading Biofuels Coalition (WNAX Radio 750) http://bit.ly/ZvSWrS
- Novozymes gets $2.5M to research turning corn waste into fuel (Sacramento Business Journal) http://bit.ly/13jj5yL
- 43 Alternative fuel vehicles we’ll see by 2015 (The Spokesman Review) http://bit.ly/11iXya3
Business & Investing
On Thursday, Cause of Action, a watchdog group connected to Representative Darrell Issa, filed a lawsuit against the Energy Department claiming loan guarantees were not granted on the basis of merit. XP Vehicle filed for a $40 million loan from the federal government in 2009 and was rejected. http://wapo.st/WxqSSM XP Vehicles suit is for $450 million and demands approval of their DOE loan application. A previous investigation spanning almost two years found that the DOE loan guarantee program was granting loans on a merit-based system. This lawsuit is evoking political dialogue similar to the dialogue heard during the Solyndra “scandal.” Issa who is also Committee Chairman of the House Oversight and Government Reform Committee, has targeted the PTC as a “waste of taxpayer money.” Lawmakers have signaled interests into holding hearings on the PTC.(PoliticoPro)
Although an extension of the PTC is great news for the wind industry, there is a growing discussion about how little the government invests in research and development and the PTC’s stop-start cycle. The American Energy Innovation Council has released a report summarizing interviews with R&D leaders. They believe the limited government role in R&D and an unstable tax credit landscape has been detrimental to the renewable energy industry. http://bit.ly/13i8Jzc
This week former White House aide, Joseph Aldy, publicly stated his belief that the ‘green’ stimulus was a great success. 720,000 jobs were created as a result of Presiden’t Obama’s $90 billion green stimulus package which also tapped billions in private investment. http://wapo.st/11mqMVE / http://bit.ly/10i03Kn
Google invested $200 million in a 161MW wind project in Amarillo Texas building on the company’s impressive renewable portfolio. Solar Mosaic, the Oakland based crowd funded solar venture, created some chatter in the headlines this week after introducing its service to the public. http://bit.ly/WINtM1 The company’s innovative finance model is attracting potential investors who can earn at least a 4.5% return on their investment to fund solar projects. http://bloom.bg/TOOOUT
Electric vehicles continue to see strong headlines as sales rose 73% in the U.S. last year and are projected to increase in 2013. http://bit.ly/10eHKG4/ http://nyti.ms/VKoiKd However, the “silence” of electric vehicles is capturing headlines as lawmakers are moving to implement a rule requiring EVs to make noises that pedestrians can hear. http://lat.ms/TZCeAP/ http://buswk.co/VKZeTB A story in the Washington Times is also pointing at a Washington state EV tax as an example of a policy idea that could spread across the country. http://bit.ly/WIR3Wq
Excel Energy has backpedaled on reviewing its membership with AWEA. http://bit.ly/U0rwdi Ben Fowke, CEO of Excel Energy issued a statement this week saying his company continues to believe wind energy is an important energy source for the company’s future.
STORIES FOR PUSHBACK
- Assessing the Green Stimulus Provisions of the 2009 Fiscal Stimulus Law (National Review) http://bit.ly/WIJgYG
- Are biofuels starving the world's poor? (Deseret News) http://bit.ly/URSnML
- How The Fiscal Cliff Bill Might Void Your Car's Warranty (AOL Autos) http://aol.it/U8Lt1B
STORIES FOR AMPLIFICATION
- California solar energy systems top 1 gigawatt (San Francisco Chronicle) http://bit.ly/XU4ObC
- The Importance of the Renewable Fuel Standard (The Motley Fool) http://bit.ly/VXltVQ
- Clean Energy And Economic Development Are Birds Of A Feather (Environmental Defense Fund) http://bit.ly/13lltnF
- Solar farm in Charles County gives SMECO new energy (Washington Post) http://wapo.st/VSAAQZ
- Solar farms leading to jobs (The Times-News) http://bit.ly/13kKpN2
- New York Governor Announces $1 Billion Green Bank And $1.5 Billion Solar Program (Think Progress) http://bit.ly/WSkjL0
- Port of Milwaukee saves on utility bills from wind turbine (Milwaukee Journal Sentinel) http://bit.ly/ZzuMNd
STORIES TO WATCH
- Mill officials say LePage’s efforts to change renewable energy policy could hurt paper industry (Bangor Daily News) http://bit.ly/ZwovBW
- In lawsuit against Energy Department, two firms claim cronyism in ‘green car’ loan program (Washington Post) http://wapo.st/VRvPa9
- Wind industry awaits tax guidance on PTC rule (Politico) http://politi.co/VOVeSg
- Con: Keep the ethanol mandate, but gradually shift from corn to biofuels (Gazette Extra) http://bit.ly/WxmjrF
- Taxpayers Sink Deeper in Solyndra Saga: Part One (Heritage Foundation) http://herit.ag/UZs8Ru
National & State Politics
- USDA program fuels renewable energy (San Antonio Business Journal) http://bit.ly/ZPu971
- California hits a renewable energy milestone (Silicon Valley Mercury News) http://bit.ly/XS5M8e
- Army on track to meet contracting goal for energy projects (Federal Times) http://bit.ly/11moIwE
- Clean Energy Vs. Tar Sands (KUTV News Utah) http://bit.ly/VodhkM
- New York's Clean Tech Challenge To California (Forbes) http://onforb.es/WFeFLC
- DOE spokesman heads for senior role in New York state AG’s office (The Hill) http://bit.ly/11mpEkE
- Baucus defends tax breaks in 'fiscal cliff' deal (Great Falls Tribune) http://gftrib.com/Wxm53L
Solar, Wind, Hydro, Biomass
- What Does 2013 Have In Store For The Solar Sector? (Forbes) http://onforb.es/SmfIoL
- Science proves wind energy is safe (Milwaukee Journal Sentinel) http://bit.ly/VOwVWR
Vehicles, Biofuels, Electrification
- API President Leaves Biofuels, Biochemicals out of his “State of American Energy” Report (Biomass Magazine) http://bit.ly/VPzllK
- USA's largest “carbon neutral” office set for San Diego (Ars Technica) http://ars.to/VUXjva
- U.S. Agriculture Secretary Vilsack to visit new King of Prussia bio-energy firm (Philly.com) http://bit.ly/UQ7diS
- Cool Springs biofuel firm raises $25 million (The Tennessean) http://tnne.ws/XpPobd
- Another Bump in the Road for Electric Vehicles (The Motley Fool) http://bit.ly/13jQk50
September 21 -- Arvada, Colorado - September 19, 2012: SkyFuel, Inc. was honored with the 2012 Technology Award at the annual Solar PACES conference, held this year in Marrakech. The award was made for the development of ReflecTech®PLUS - a high reflectance, durable, silvered polymer film designed to reduce the lifecycle cost of parabolic trough solar fields. ReflecTech®PLUS is the first reflective film that has proven to be durable outdoors for more than 30 years and incorporates an abrasion resistant coating. The film was developed by ReflecTech, Inc. in collaboration with the U.S. National Renewable Energy Lab. >>View Article
September 10 — The Heat is Power Association applauds President Obama for his commitment today to industrial energy efficiency through an Executive Order setting a national goal for deploying 40 gigawatts of new, cost effective industrial efficiency projects including combined heat and power (CHP) and waste heat to power (WHP) by 2020. >>View Article
Submitted By ACORE Member, The Heat is Power Association
There is a largely unheralded fuel that is continuously produced at nearly every energy intensive industrial process in the
What is this mystery fuel? Waste Heat. Recoverable waste heat is produced around the clock in substantial quantities each day. If harnessed to produce power in the US, waste heat could generate as much as 10 GW of emission-free electricity, enough to power 10 million American homes, provide $3 billion in savings for US industry, and spur the creation of 160,000 new American jobs.