Energy recovery
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Energy recovery includes any technique or method of minimizing the input of
In some circumstances the use of an enabling technology, either daily
Principle
A common application of this principle is in systems which have an exhaust stream or waste stream which is transferred from the system to its surroundings. Some of the energy in that flow of material (often
System approach
An energy recovery system will close this energy cycle to prevent the input power from being released back to nature and rather be used in other forms of desired work.
Examples
- Heat recovery is implemented in heat sources like e.g. a cooling waterfrom the process is sold for heating of homes, shops and offices in the surrounding area.
- Regenerative braking is used in electric cars, trains, heavy cranes etc. where the energy consumed when elevating the potential is returned to the electric supplier when released.
- Active pressure reduction systems where the differential pressure in a pressurized fluid flow is recovered rather than converted to heat in a pressure reduction valve and released.
- Energy recovery ventilation
- Energy recycling
- Water heat recycling
- Heat recovery ventilation
- Heat recovery steam generator
- Cyclone Waste Heat Engine[1]
- Hydrogen turboexpander-generator
- Thermal diode
- Thermal oxidizer
- Thermoelectric Modules
- Waste heat recovery units
Electric Turbo Compound (ETC)
Electric Turbo Compounding (ETC) is a technology solution to the challenge of improving the fuel efficiency of gas and diesel engines by recovering waste energy from the exhaust gases.
STES
- At a foundry in Sweden waste heat is recovered and stored in a large mass of native bedrock which is penetrated by a cluster of 140 heat exchanger equipped boreholes (155mm diameter) that are 150m deep. This store is used for heating an adjacent factory as needed, even months later.[2]
- The Drake Landing Solar Community in Alberta, Canada uses STES to recover and utilize natural heat that otherwise would be wasted. The community uses a cluster of boreholes in bedrock for interseasonal heat storage, and this enables obtaining 97 percent of the year-round space heating from solar thermal collectors on the garage roofs.[3][4]
- Cold winter temperatures can be recovered by circulating water through a dry cooling tower and using that to chill a deep aquifer or borehole cluster. The chill is later recovered from the storage for summer air conditioning.[5] With a coefficient of performance (COP) of 20 to 40, this method of cooling can be ten times more efficient than conventional air conditioning.[6]
Environmental impact
There is a large potential for energy recovery in compact systems like large industries and utilities. Together with
- Reduced number of coal-fired power plants
- Reduced airborne particles, NOx and CO2 – improved air quality
- Slowing or reducing climate change
- Lower fuel bills on transport
- Longer availability of crude oil
- Change of industries and economies not fully researched
In 2008 Tom Casten, chairman of Recycled Energy Development, said that "We think we could make about 19 to 20 percent of U.S. electricity with heat that is currently thrown away by industry."[7]
A 2007 Department of Energy study found the potential for 135,000 megawatts of
It is difficult to quantify the environmental impact of a global energy recovery implementation in some sectors. The main impediments are:[citation needed]
- Lack of efficient technologies for private homes. Heat recovery systems in private homes can have an efficiency as low as 30% or less. It may be more realistic to use energy conservation like thermal insulation or improved buildings. Many areas are more dependent on forced cooling and a system for extracting heat from dwellings to be used for other uses are not widely available.
- Ineffective infrastructure. Heat recovery in particular need a short distance from producer to consumer to be viable. A solution may be to move a large consumer to the vicinity of the producer. This may have other complications.
- airline industryis known in this field.
See also
- Efficient energy use
- Energy conservation
- Energy recycling
- DWEER
- List of energy storage projects
- Mechanical vapor recompression
- Pinch analysis
- Waste-to-energy
References
- ^ Cyclone Power Technologies Website
- ^ Andersson, O.; Hägg, M. (2008), "Deliverable 10 – Sweden – Preliminary design of a seasonal heat storage for ITT Flygt, Emmaboda, Sweden", IGEIA – Integration of geothermal energy into industrial applications, pp. 38–56 and 72–76, retrieved 21 April 2013
- ^ Wong, Bill (June 28, 2011), "Drake Landing Solar Community" Archived 2016-03-04 at the Wayback Machine, IDEA/CDEA District Energy/CHP 2011 Conference, Toronto, pp. 1–30, retrieved 21 April 2013
- ^ Wong B., Thornton J. (2013). Integrating Solar & Heat Pumps. Archived 2013-10-15 at the Wayback Machine Renewable Heat Workshop.
- ^ Paksoy, H.; Stiles, L. (2009), "Aquifer Thermal Energy Cold Storage System at Richard Stockton College" Archived 2014-01-12 at the Wayback Machine, Effstock 2009 (11th International) – Thermal Energy Storage for Efficiency and Sustainability, Stockholm.
- ^ Willemsen, G. 1998. Open-loop geothermal heat pump systems in the USA and aquifer cold storage in the netherlands – similarities and differences. The Second Stockton International Geothermal Conference. March 16 and 17, 1998
- National Public Radio.
- ^ Bruce Hedman, Energy and Environmental Analysis/USCHPA, "Combined Heat and Power and Heat Recovery as Energy Efficiency Options", Briefing to Senate Renewable Energy Caucus, September 10, 2007, Washington DC.
- ^ "Clean Energy Technologies: a Preliminary Inventory of the Potential for Electricity Generation, Lawrence Berkley National Laboratory, 4/05" (PDF).
- ^ "The Energy Information Administration, Existing Capacity by Energy Source, 2006".
- U.S. Environmental Protection Agency. Archived from the originalon 2011-12-18.
- U.S. Energy Information Administration.