"Christian McArdle" wrote in message
...
They will produce electricity intermittently. When the thermal store is
up
to temp and no heat is demanded from CH and DHW, then you draw from the
grid. It is claimed that over 50% of all electricity will be generated
in
the home using these units and 25% cheaper to run in both gas and
electricity, as you also sell electricity back to the power company.

A bit of careful design with the heatbank could get better than this. If
you
have space to oversize the cylinder, you could get it to only demand heat
when less than 1/2 full. Then it could be available for electricity until
full. I haven't seen the specs, but I presume the CHP's heat output when
demanding electricity only would be around 3kW when producing 1kW of
electricity, so you could get several hours of electricity out of it
before
the heat bank is 100% satisfied, requiring the motor to be shut down.

This is what Gledhill hope to do. The store literally stores heat that would
be otherwise wasted. The CHP Stirling units alone, don't produce that much
heat, say compared to a 25kW boiler, so it could trickle charge the store
retaining heat while producing electricity. The Microgen has an additional
burner to boost the Stirling engine. The control system and sizing of the
store is essential in gaining maximum efficiency. The scenarios of calling
for electricity and no CH or DHW or DHW calling and no electricity called,
ect, have to be thought out. A self adaptive control system remembering the
demand of the house, would be likely.