IMM wrote:

"Ian Stirling" wrote in message
...
IMM wrote:

"Christian McArdle" wrote in message
. net...
Has anyone heard of Micro Combined Heat and Power units. I am made
to
believe that these are boilers that also generate their own
electricity
and
are highly efficient.

I hadn't realised that they had gone into production yet. I think
they're
a
great idea, but personally, I prefer to avoid 1st generation products.
If
snip
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.

Personally, mine would rapidly grow a small battery bank, so it could be
operated entirely off-grid, in case of power failure, and to provide
for larger surges than 1Kw.

No need. The Microgen can work off the grid giving 1kW 1kW will provide
all essential services to a house: fridge, lights, power for CH, DHW, etc.

1Kw is not enough.
A fridge and freezer will easily use 1Kw (if they happen to start at
once.) Plus, with the microgen, you need power to start it.


I'd also be looking at a small gas storage tank that could be plumbed
up to the boiler for a mains gas outage too,

I'm not sure if you can store natural gas. You can but they may object. It
may be cheaper to have a natural gas and an LPG CHP boiler unit. The LPG
can be run off large gas bottles as this would be for backup only, so no
need for an expensive to buy and rent large LPG tank laying there consuming
money.

I was more thinking of a couple of large propane cylinders, to cover short
outages.
(after investigating if I can safely compensate for the different gas
properties with different feed pressure, or if I'd need to swap nozzles)

as well as considering
a large thermal store.

Good idea. And run very low temp underfloor heating from it.