1. Modern Coal Fired Power Plants are “out in the boonies” because they are constructed near to the coal mine. It is much more energy efficient to move the electricity than the coal.

2. Transmission losses for a well designed high voltage transmission system is about 3.5% or less per 1000 km (http://www.greenpeace.org/raw/content/international/press/reports/energyrevolutionreport.pdf Fig4.2 P32). The 7-8% refers to both transmission and distribution. If you have a small scale generator system that feeds the local grid it uses the low voltage distribution where the greatest losses are, so the only saving for local distributed generation is the 3% for HV transmission. This is often less than efficiency gain that is achieved by the economies of scale for large power plants.

3. Moving gas is difficult as it is a compressible fluid. The 2% you quoted is a common mistake and usually refers to the metering loss in the large pipeline system. This is the actual gas that is lost. Gas also has considerably more mass than electricity and the energy used to compress the gas, and heat it unnecessarily through compressor inefficiencies, plus the pipeline friction loss is of the order of about 10-12% (http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=ASCECP000361041073000009000001&idtype=cvips&gifs=yes&ref=no). It worth noting that piping and pumping any fluid around comes at a high energy cost if the distance become large. It is often more efficient to use electricity and a heat pump as noted by ncbill, in large commercial installations a COP of 7-8 is achievable.

4. Actual gas loss in the local distribution system is much higher than for electricity. If there is an electrical fault the circuit breakers trip, for gas the fault tolerance is much higher. A walk around a neighbourhood served by gas on a still evening and the odour of the gas will confirm this.

5. Natural Gas is a fossil fuel and while it is a little better than coal it still has a large carbon impact. The carbon impact is 21 times higher for gas that escapes without being burnt (56 times if you consider the next 20 years time horizon rather than the 100 year normally used http://unfccc.int/ghg_data/items/3825.php). If you simply compare the molecular weights of Carbon (coal) 12 and Methane CH4 16 to the Carbon dioxide CO2 44 produced then 1 tonne of pure carbon produce 3.66 tonnes of CO2 and 1 tonne of Methane produces 2.75 tonnes of CO2.

6. The electricity wires are still the only way to economically deliver zero carbon energy, we just have to make more of the electricity with zero carbon sources ie renewable, geothermal and perhaps nuclear.

So in conclusion if any technology relies on natural (fossil fuel) gas replacing coal it is dubious how much better it actually is, perhaps it’s like going on a diet where you replace deep-fried Mars bars with deep-fried Twinkies.

In the UK there was a company called Microgen Energy (part of the BG Group – formerly British Gas) that was trialling a Micro-CHP unit based on a Sterling engine. Unsuccessfully it seems, since Microgen was wound up in 2007.

A little research found another Sterling unit produced by the New Zealand company WhisperGen (www.whispergen.com/).

http://www.fossil.energy.gov/programs/powersystems/fuelcells/fuelcells_solidoxide.html

But a fuel cell is not a condensing steam turbine.

Small-scale turbines (for CHP) would indeed have lower electric power efficiency than a large central fossil fuel-fired turbine.

His point is that since the best heat pumps have a COP over 4 (for every unit of electricity expended you get 4+ units of heat) we should use your fossil fuels to generate electricity as efficiently as possible for heat pumps instead of burning the fossil fuels directly for heat.

The fuel cell generates heat as a byproduct of consuming the fuel for electricity production – we’re not affecting the efficiency of the fuel cell by capturing the waste heat for water heating or space heating.

http://www.cbsnews.com/video/watch/?id=6228923n

Can I hit it very hard with a baseball bat WHILE soaking it with water from a hose without it exploding?

If so, sign me up. If it can’t handle a little abuse, I want no part.

In it, David MacKay, talks about combined heat and power production and concludes that getting the heat from a power plant hurts the efficiency of power production, especially when considering how much more useful electricity is over heat.

jhs,
Solid oxide fuel cells operate at around 800-1000 deg C. yeah it produces heat. However it is well insulated so that the external skin probably doents get very hot. That is why using it as a CHP unit would be critical to make good efficiency claims.