QUESTION = If heat is one of the most abundant energy sources, how come we don't have an efficient way of harnessing it yet?

GENERATION = That's not how electricity works. A battery uses chemical reaction to generate electricity. A car engine uses mechanical force to drive a piston. There's way too much work for a battery to perform effectively. Batteries are far more efficient for moving energy around than a motor. If we could produce a machine that also carried that amount of work (and to a much greater degree, directed it) then we could have electricity flowing all the time. The problem is that the energy required to provide this electricity takes more energy to turn a wheel, so we are not making more than we already have. We just don't have the resources to make the electricity. So if you want to harness the largest amount of energy you can, you will need to find a way to efficiently move it. I find that there is no solution for how to do that, because it requires moving energy out of the system. The biggest question then is, why can't we create a mechanism to move it out of the system quickly? That's a really interesting question, because we can't even get really close. That's currently science-y. 

RETRIEVAL #0 = Energy recovery---in some sectors. The main impediments are: BULLET::::- 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. BULLET::::- 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. BULLET::::- Transport sector is not ready. With the transport sector using about 20% of the energy supply, most of the energy is spent on overcoming gravity and friction. Electric cars with regenerative braking seem to be the best candidate for energy recovery. Wind systems on ships are under development. Very little work on the airline industry is known in this field. Section::::See also. BULLET::::- Efficient energy use BULLET::::- Energy conservation BULLET::::- DWEER BULLET::::- List of energy storage projects BULLET::::- Mechanical vapor recompression BULLET:::: 

RETRIEVAL #1 = Energy development---28 gigawatts of direct geothermal heating capacity is installed for district heating, space heating, spas, industrial processes, desalination and agricultural applications in 2010. Geothermal power is cost effective, reliable, sustainable, and environmentally friendly, but has historically been limited to areas near tectonic plate boundaries. Recent technological advances have dramatically expanded the range and size of viable resources, especially for applications such as home heating, opening a potential for widespread exploitation. Geothermal wells release greenhouse gases trapped deep within the earth, but these emissions are much lower per energy unit than those of fossil fuels. As a result, geothermal power has the potential to help mitigate global warming if widely deployed in place of fossil fuels. The Earth's geothermal resources are theoretically more than adequate to supply humanity's energy needs, but only a very small fraction may be profitably exploited. Drilling and exploration for deep resources is very expensive. Forecasts for the future of geothermal power depend on assumptions about technology, energy prices, subsidies, and interest rates. Pilot programs like EWEB's customer opt in Green Power Program show that customers would be willing to pay a little more for a renewable energy source like geothermal. But as a result of government assisted research and industry experience, the cost of generating geothermal power has decreased by 25% over the past 

RETRIEVAL #2 = Electric heating---converted to building heat (the only exception being fan noise and indication lights which demand very little electricity and virtually none at all when compared to the extremely large energy draw of the heating itself). However, if a power plant supplying electricity is included, the overall efficiency drops drastically. For example, a fossil-fuel power station may only deliver 3 units of electrical energy for every 10 units of fuel energy released. Even though the electric heater is 100% efficient, the amount of fuel needed to produce the heat is more than if the fuel were burned in a furnace or boiler at the building being heated. If the same fuel could be used for space heating by a consumer, it would be more efficient overall to burn the fuel at the end user's building. On the other hand, replacing electric heating with fossil fuel burning heaters, isn't necessary good as it removes the ability to have renewable electric heating, this can be achieved by sourcing the electricity from a renewable source. Variations between countries generating electrical power affect concerns about efficiency and the environment. In France 10% is generated from fossil fuels, in Britain 80%. The cleanliness and efficiency of electricity are dependent on the source. In Sweden the use of direct electric heating has been restricted since the 1980s for this reason, and there are plans to phase it 

RETRIEVAL #3 = Energy harvesting---electric grid that fixes itself when blackouts hit. For many decades, scientists and experts have argued that the best way to fight congestion is intelligent transportation systems, such as roadside sensors to measure traffic and synchronized traffic lights to control the flow of vehicles. But the spread of these technologies has been limited by cost. There are also some other smart-technology shovel ready projects which could be deployed fairly quickly, but most of the technologies are still at the development stage and might not be practically available for five years or more. Section::::Devices.:Pyroelectric. The pyroelectric effect converts a temperature change into electric current or voltage. It is analogous to the piezoelectric effect, which is another type of ferroelectric behavior. Pyroelectricity requires time-varying inputs and suffers from small power outputs in energy harvesting applications due to its low operating frequencies. However, one key advantage of pyroelectrics over thermoelectrics is that many pyroelectric materials are stable up to 1200 ⁰C or higher, enabling energy harvesting from high temperature sources and thus increasing thermodynamic efficiency. One way to directly convert waste heat into electricity is by executing the Olsen cycle on pyroelectric materials. The Olsen cycle consists of two isothermal and two isoelectric field processes in the electric displacement-electric field (D-E) diagram. The principle of the Olsen cycle is to charge 

RETRIEVAL #4 = Electricity---electric heating. While this is versatile and controllable, it can be seen as wasteful, since most electrical generation has already required the production of heat at a power station. A number of countries, such as Denmark, have issued legislation restricting or banning the use of resistive electric heating in new buildings. Electricity is however still a highly practical energy source for heating and refrigeration, with air conditioning/heat pumps representing a growing sector for electricity demand for heating and cooling, the effects of which electricity utilities are increasingly obliged to accommodate. Electricity is used within telecommunications, and indeed the electrical telegraph, demonstrated commercially in 1837 by Cooke and Wheatstone, was one of its earliest applications. With the construction of first intercontinental, and then transatlantic, telegraph systems in the 1860s, electricity had enabled communications in minutes across the globe. Optical fibre and satellite communication have taken a share of the market for communications systems, but electricity can be expected to remain an essential part of the process. The effects of electromagnetism are most visibly employed in the electric motor, which provides a clean and efficient means of motive power. A stationary motor such as a winch is easily provided with a supply of power, but a motor that moves with its application, such as an electric vehicle, is obliged to either carry along a power source such as a battery, or to 

RETRIEVAL #5 = Hydrogenase---the challenge in the development of technologies for the capture and storage of renewable energy as fuel with use on demand. The generation of electricity from H is comparable with the similar functionality of Platinum catalysts minus the catalyst poisoning, and thus is very efficient. In the case of H/O fuel cells, where the product is water, there is no production of greenhouse gases. Section::::Biochemical classification. BULLET::::- EC 1.12.1.2 hydrogen dehydrogenase (hydrogen:NAD oxidoreductase) BULLET::::- EC 1.12.1.3 hydrogen dehydrogenase (NADP) (hydrogen:NADPH oxidoreductase) BULLET::::- EC 1.12.2.1 cytochrome-"c" hydrogenase (hydrogen:ferricytochrome-"c" oxidoreductase) BULLET::::- EC 1.12.5.1 BULLET::::- EC 1.12.7.2 ferredoxin hydrogenase (hydrogen:ferredoxin oxidoreductase) BULLET::::- EC 1.12.98.1 coenzyme F hydrogenase (hydrogen:coenzyme F 

RETRIEVAL #6 = Energy security---up water sources we could essentially use the steam creating from the heated water to power machines, this option is one of the cleanest and efficient options. Hydro-electric which has been incorporated into many of the dams around the world, produces a lot of energy, and is very easy to produce the energy as the dams control the water that is allowed through seams which power turbines located inside of the dam. Biofuels have been researched using many different sources including ethanol and algae, these options are substantially cleaner than the consumption of petroleum. "Most life cycle analysis results for perennial and ligno-cellulosic crops conclude that biofuels can supplement anthropogenic energy demands and mitigate green house gas emissions to the atmosphere". Using oil to fuel transportation is a major source of green house gases, any one of these developments could replace the energy we derive from oil. Traditional fossil fuel exporters (e.g. Russia) struggle to diversify away from oil and develop renewable energy. Section::::See also. BULLET::::- By area BULLET::::- Cebu Declaration on East Asian Energy Security BULLET::::- Energy Independence and Security Act of 2007 BULLET::::- Energy Security Act BULLET::::- Energy security of Afghanistan BULLET::::- Energy security of the