My neighbor has very kindly done a meter reading for me.
I have a 12kVA supply and use 5000kwh per year (average over 2 years) and pay approx 104 euros in total per month.
I will check with www.energie-info.fr to see what savings can be made.
An English speaking helpline would be useful but not essential - are there any providers that should be avoided?
Do I need to notify EDF if I change provider or is this all automatically done by the new provider?
Thought about antifreeze but like corrosion inhibitor no easy way into the system - basically the system has a valve which lets water in from the mains in and a drain cock but is otherwise completely sealed (there is a pressure expansion vessel, obviously).
Heat tape is an intriguing suggestion, but my gut reaction would be that it will be difficult to add at this stage (it would have been easy to add it while the system was being put in).
I have signed up with another supplier on a fixed tariff and hopefully saved 33 Euros per month.
Thanks @James for raising this topic.
Care to spill the beans Mat?
Quite simply I was over paying with EDF on an expensive tariff - the comparison website found a cheaper tariff for me.
12kW is a lot unless your house has a huge demand for electricity. If you were paying equal monthly payments without submitting a reading how does anybody know what your electricity consumption was?
Itās 60A which is a good bit less than the typical supply in the UK which is normally 100A (24kVA).
Itās easy to go over 12kW in a modern home.
We have the heat pump (4-5kW when running 6kW peak), induction hob (up to 7kW), oven (5kW), dishwasher and washing machine (1.5kW each) , as well as the usual higher power kitchen stuff - microwave, kettle, coffee machine etc - as well as TV, gadgets and lightning etc (though lots of LED fitments so consumption from those trivial).
The previous owner admitted that the heating regularly tripped the breaker when the supply was only 6kW.
I manage quite happily on 6kW, 12 is a big step up.
Your wood heating will make a huge difference, Iām not surprised you manage on 6kW but by UK domestic supply standards 6 is tiny and 12 still modest.
Iād rather have 15 or 18kW to be honest as, at least in theory, if the oven & hob are on and the heating kicks in it could trip everything out. Not happened yet and increasing the supply means a lot of expense as weād have to go to three phase. When I was arranging the increase from 6 to 12 the girl on the phone asked me what electrical stuff we had and then told me her computer recommended a 15kW supply. My response - ābut that will cost a lot wonāt it?ā was met with an āoh, <pause>, yesā - I never did ask but even she didnāt try to get me to take 15kW 
The only difference is the abandonment, unit cost is the same, just the silly way the french do it. You have to pay extra for just the potential to use more which might only do in the depths of winter or maybe a couple of times a month.
My single woodburner backs up my principle electric heating which runs 24/7 on a thermostat throughout the winter months. My electric water heater runs 365 days a year. I only use my induction hotplate during the summer months. Iām not sure what the average U.K. house owner has to need such a large supply as I left there over half a lifetime ago so my yardstick is what I need here and now.
When you made your first post four days ago I thought that your average monthly electric costs were huge for a holiday home as they all but match what I pay for my similar sized stone house that I live in all year round.
The difference in cost between 6kW and 12kW is about 25 euros per year on the tariff we are on.
Since some bad experiences in gites of having too low a power where you had to be very careful as to what was switched on at the same time otherwise it would trip - we took the advice of our electrician to ensure that we (or our guests) would not have the same problems. It was daft that putting the toaster and kettle on the same time would trip the system.
We know exactly what our consumption was over the past 2 years as the meter was installed then and started at zero - quite evenly we are using 5000kWa per year.
Ha! yes, so did I!
For a fair comparison, of course youād have to add in the cost of your wood.
Heating is probably our biggest single use. Leaving the system on pretty much full blast for 6 weeks last year didnāt help but Iām hoping that will not be a typical year, both from the point of view that it was a colder than normal winter and the fact that I now know the system a bit better (it has rather been left to itself while we got on with other work).
Some things though Iām stuck with. For one, even leaving it on standby seems to present a load of about 150W - this really adds up over the year (at least 700 units) and I donāt think I can do much about that except turn it off completely. I might be willing to do that May to September but not otherwise without draining the system (and regular changes of water in the system would bring its own issues). Leaving tāinternet on for remote access will up the 'leccy bill as well (Iām hoping that will be less than 50W though).
As I said in previous posts heat pumps are probably brilliant for low temperature high surface area heating systems such as underfloor or pool heating but they are severely compromised by the high flow temperatures needed for hot water or traditional radiators. Thereās almost always a bit of gain though so they are better using electricity alone (which has always been a very expensive way to heat).
At least Iām still within our āoperational budgetā for the house and when we are there itās easy enough to get the place cosy. I feel much more for Maddie who is clearly struggling with a heating solution which is both expensive and ineffective and it sounds like she doesnāt have the capital resources to easily get out of her current situation.
Worked out over the year my wood costs me about ā¬1 a day.
And your electricity bill?
Less than 10% more than yours.
āLess than 10% more than yoursā
So, disregard the electricity for a second.
The difference is the wood and the fact that electricity is really not a great way to heat a house.
How much energy is in wood? - no personal experience so I find the following calculation almost hard to swallow and I imagine the uncertainties are huge but letās stick with it a moment, The published figure for White Oak is 24MBTU per cord. Allowing for that being a 3.6m3 cord that is 20MBTU per 3m3 corde.
1kWh is 3412 BTU, so 20MBTU is 20000000/3412 or 5861kWh, assuming 75% burner efficiency thatās the equivalent of 4400kWh of electricity. At plain tariff bleu prices that is 651ā¬ worth of electricity.
You said your wood was 1ā¬ per day so 365ā¬ a year and you pay 150ā¬ a corde so 2 and a third cordes per year worth 1151ā¬ of electricity.
Iāll assume 10% more than my ālowā year not my high year - you spent 1151+580-100 or approx 1631ā¬ (in electricity terms) on fuel.
I spent 529-137 or 392ā¬, we were there about 6 weeks in 2016 so use is actually twice yours for the weeks weāre there. I could take outthe background stand-by use for the heating but canāt be bothered.
Intermittent heating is very inefficient (it takes a day and a half of the heating running more or less flat out to turn the cold, slightly damp house to a warm dry one which is a big fraction of a one week stay) so thatās probably acceptable. We also always use the induction to cook (having no alternative if itās not warm enough to get the BBQ out).
So, yes, weāre using more than you but not loony amounts more.
100 & 137 being the approx standing charge for plain tariff bleu, in case you were wondering where I got those from.
I really donāt understand your calculations. Have I got it wrong? Yours is a holiday home, I live here all year round. Am I correct? If so Iām glad you think you are getting good value for your six weeks. Iām quite happy with what I pay for my 52. I pay a bit more per month for electricity than you when averaged out over the year plus the wood. The calorific value of that wood in terms of electricity is irrelevant as Iām only interested in the cost. I spend just over ā¬1000 in fuel, far less than the ā¬1600+ that you suggest. That figure includes all the standing charges.
When my house was a holiday home I paid much, much, much less despite using the house for at least 12 weeks of the year.
Just trying, possibly not terribly accurately or successfully to make a meaningful comparison between your mixed fuel use and my electricity-only use. The only way to do so is to convert to a common base which might as well be kWh of electricity, thence to price.
Itās not meant to be the literal amount that you are spending. Wood is cheaper, per kWh, than electricity is (most fuels are) so the idea is to work out how much heat you get from your wood, then work out how much youād have to spend on electricity to get the same amount of heat.
Sure, you arenāt going to bother with it on a day to day basis but itās going to come up in any comparison between different fuels.
Good value? No, but not terrible value either.
Itās been interesting to do the comparison and calculations. If you canāt tell, I like data & numbers and manipulating them to answer questions