It is a course a very good idea. It is one of the least costly ways to reduce CO2 and produce energy. It is a bit late to market when HONDA and others have about 100,000 units in operation, but they are all too expensive so compettition is needed. It looks big but the contribution seem almost small enough. It should have been called VOLKSSTROM. ..HG..

That's exactly what I was going to post about next Henrik ... and it's being worked on already. I just don't know what the emissions are like in the nat gas to hydrogen proces. http://www.gastechnology.org/webroot/app/xn/xd.aspx?it=enweb&xd=4reportspubs%5C4_8focus%5Cnaturalgastohydrogenfuelingstations.xml

Germany has already proven this would work using biogas fueled farm-based CHPs-
http://www.unendlich-viel-energie.de/en/electricity/combined-power-plant.html
So adding home-based CHPs to the grid is just logical.
In 2007, produced 22.4 billion kWh of biogas electricity, out of a 594.7 billion kWh total.

http://www.kombikraftwerk.de/index.php?id=27

Lets not assume that all conventional power plants cannot adjust their output quick enough to compensate for power generation fluctuations from Wind and Sun and other sources.

Hydro power plants (currently suplying 98% of our e-power)can adjust their output rather quickly and store the unused power (water) in their huge existing reservoirs at no extra cost.

It is very easy to forecast Sun and Wind power production. This would give plenty of time to adjust Hydro ouput when required.

Hydro producers will have to get used to be secondary sources (+ storage) of power and let other more volatile sources be used as primary sources.

NG power plants could play a similar back up secondary role where Hydro power is not enough.

Ah yes but it's that when there is really no other way to spend the produced electricity thing that's the kicker.

There are just too many ways to store electricity; pumped hydro, batteries[For grid storage we could use both BEV fleets and stationary flow batteries: Examples of redox flow batteries are the vanadium redox flow battery, polysulfide bromide battery (Regenesys), and uranium redox flow battery. Hybrid flow batteries include the zinc-bromine, cerium-zinc and all-lead flow batteries.], Compressed Air Energy Storage (CAES)[The need for pressurized vessels or for mining can be obviated by placing the pressurized air underwater in flexible containers (e.g. plastic bags) at the bottom of deep lakes or off sea coasts with steep drop-offs.] and Transport[Utilities routinely move large quanities of electricity over grid interties.]

This sounds like cogeneration for an apartment building...preferably someplace cold that needs heating, or lots of hot water. Part of the challenge is that the times of day you need electricity vary somewhat from the times you need heat.

This is a fine thing where you need it. Actual efficiency results tend to be quite a bit less than theoretical.

@Nordic
For example Germany has aprox 20% of electric load provided by solar.
Actually, by 2008 the overall electricity production by ALL renewable sources[not just solar] was only 15% of gross electricity production in Germany.

@HealthyBreeze
Actually the article says: "While the ZuhauseKraftwerk will only generate power on demand, the heat produced at the same time will be stored, allowing reliable supplies of heating energy and warm water to the building at all times."

It's much easier to store heat than electricity; many of the newer green buildings in my area already store solar and/or waste heat using ground-loop heat pumps.

Would be a good match for solar thermal, which could provide hot water in the summer when heating and lighting demands are lower. Then on cold winter evenings when heat and electricity demands are high the unit can supply both.

Stick some wheels on it and it can be your range extender too.

Others and the article by the engineer-poet has just pointed out something that has been ignored for many years. "Furnaces" can be built to run on natural gas and get as much as %200 efficiency or more. An engine that runs on natural gas can operate a heat pump compressor directly and with various heat exchangers and heat storage units get double the heat at least that is gotten by a standard unit. Some engine heat can be stored in the earth for later use when temperatures get really cold.

The Capstone C30 unit is of similar size but has only one major moving part, and runs with air bearings.

This is a unit not highly suited to single separate homes, but smaller units like the HONDA CHP should be required in every home. The efficiency of waste heat collection should be required to be improved. The Freewatt name is misleading; you are getting free heat but you have to pay for the power by burning gas. Gas prices should be adjusted for use in such machines relative to the prices utilities get when they burn gas.

There is also a small unit called the 'lion' for single dwelling use that has a built in steam engine, and Enatec is in a consortium that has been testing freepiston stirling units for over five years.

The financing model is more attractive than some, but all such units are relatively expensive. but they are all cheaper than solar and a better investment of society's money than solar cells.

Excellent project. True, these type units will cost-out better in colder climates. But at least we will have a real world demonstration of NG-fired residential CHP.

Eventually these units will be replaced by SOFCs able to burn unreformed NG (Bloom Box e.g.) Eventually NG can be replaced by H2 from coal gasification or new forms of high efficiency electrolysis. Considering that H is the most abundant element in the known universe - it makes sense to focus on ways to best utilize it in energy systems.

Congratulations to LichtBlick and VW for forming this partnership and moving the distributed energy concept into a real world demonstration. It is just the right time to start down this path.

Still missing is the chiller component which would make the concept viable in hot sunbelts.