On 24 Dec, 21:22, Andy Hall wrote:
On 2007-12-24 15:29:23 +0000, said:



On 24 Dec, 15:16, andrew heggie wrote:
On Mon, 24 Dec 2007 07:09:30 -0800, tom.harrigan wrote:
aga suggest you need 47.5kg of
solid fuel to get 220kWh. Unless I've done something wrong, that makes
it about 70% efficient.

I haven't checked your maths, nor do I know the calorific value of your
fuel but coke burning devices always look good because the LHV
and HHV are the same. My beef with the aga is that it gives you the heat
when it wants to. Now this is fine with solid fuels because they all have
this thermal inertia problem but it's an unnecessary restriction when
burning inherently "better" fuels like gas or oil.

AJH

According to Wikipedia, coal is about 6.67 kWh/kg. According to Aga
you need 47.5kg of fuel a week. My only issue with agas is that when
you want to cook, but don't want the heat all day, that's when you
start to waste money.

No you don't. The whole point of the massive heat store is that the
average over the day is very small and there is plenty in reserve for
cooking. The few hundred watts of released heat contributes to the
space heating as well as being a very effective way of drying
slobberadors, Maine coons and chilis from the greenhouse.


Yes you do. If you care about needlessly throwing heat out the window,
then the 220kWh (270kWh for the 4 oven) it takes to run an aga a week
may be of some concern to you. The vast majority of that energy is not
used for cooking. Your aga will be giving off at least a kW of "waste"
power all the time it is on - which is all the time. If someone had a
normal electric cooker, but left a 1kW electric heater on all the time
in their kitchen in case a wet dog walked past, you might be forgiven
for thinking they were a bit daft!

But for gas it's even worse! According to Aga, a 2 oven uses 425kWh of
natural gas a week, to produce 220kWh of heat. I suppose you could
take the view that you are wasting so much energy anyway, what's the
point in wasting a bit less by fitting a more efficient burner. A 52%
efficient burner is pretty shocking considering you can get range
cookers every bit as good as an aga with condensing burners nowadays.

If I could afford to run one, I'd probably get
one. At the moment I'm after a solid fuel cooker that's a bit more off-
and-on-able. It's quite difficult getting information on heat up
times, but I reckon the Stanley Errigal should heat up fairly quickly,
though I do prefer the look of the Rayburn 300W or Esse woodfired
cooker.


The problem with rapid heatup is that there is rapid cooldown as well
and it becomes very difficult to regulate temperature.

I hope to find a cooker that will heat up in an hour or so. That way
in milder weather I'll let the fire go out when I don't need it. I
imagine I could light it when I got in from work, and when I'm ready
to cook, it will be too. It's up to me whether I keep the fire going
till morning or all day.

What do you recommend for a second cooker by the way?

T