BigD

Thanks to everyone who bothered to reply.
I am none the wiser about Running Cost ?
Has anyone ever done a comparison ?
Kind Regards

Fred James

A comparison with what?

twyntub

I guess you mean specific cost i.e. per kWh.

Traditional 'electric heater' gives out 1kW for every 1kW you put in or thereabouts. Cost is 8c per kWh.

Gas estufa running at 1kW, burns 0.073kg of butano in an hour. Assuming 12.70 or thereabouts for a bottle, that's 7.4c per kWh, but I have to get the replacement bottle by driving to a garage 14km away. That's a 28km round trip, at 5.5l/100km in my diesel estate and 1.05 euro per litre. Each bottle provides around 172 kWh, so the cost of driving to get a new one adds 0.94 cents per kWh. Cost is 8.3c per kWh.

Air-con is around 3 times the efficiency (or greater). Assuming three times, every 1kW of output requires 333 watts of input. Costs is 2.66c per kWh.

Wood very much depends on price. Many people around here just carry it home so cost is 0c per kWh.

Does that answer your question?

jason1970

hi we had a company called eurocooling install a inverter system whats uses 30% less power on electrics they can help

Solarwhizz

Numbers dont stack up,

1st You probably get your gas in the course of other chores, so it would be unfair to include in comparison , unless you take a very small amount as a proportion of collection cost, for practical purposes it is not worth bothering.
2. A modern day Aircon unit/heatpump, say a Panasonic with inverter will consume 800w or less per hour whilst providing in excess of 3KW of heat in air format. this means running cost would be 0.08KWh, the cost of a KWH excluding fixed costs (as you pay these anyway) is approx 0.09c therefore running cost per hour would be about 0.7C. Then take into account dispersion efficiency,with A/c you are exiting hot air, which heats the air in and around the room and more importantly yourself, as you are in direct contact with the air so therefore heatexchange to you is more efficient than say a radiator which is also heating the walls, the furniture etc in its radiated path. it is also true that hot air rises so there would be some loss of heat, especially in high ceiling buildings, but as this is true to a degree with radiators, I would suggest that this is equal,
3. if you accept 2.66c per hour as a heating cost for 3KW energy, that means for a ten hour day your cost would be 26.60c or 798€ per month. ( I frequently run my A/C units on Heat allday and have seen nothing like this in running costs)

I have a wood burner with back boiler feeding 5 radiators, cost per annum historically has been around 400.00€

I have two AIrcon units with heatpumps installed and have used these this year, in lieu of thewoodburner when it suits and have this year so consumed about 250€ or wood, and my electricity bills have gone up on average sinc Nov by about 32.00€ per month(this also includes extra cooking etc as we tend to do in winter). So all in I would probably say that the costs are about the same, I lose with A/C on other rooms, IE hall bathroom and spare bedrooms as the radiators are not running from the back boil!! However the Aircon offers great convenience and almost instant heat.

In my view heatpumps are a very efficient C/H source. and the running cost would be comparable if not better than others but offering more convenience benefits (Inc A/C in the summer)

Fred James

I think you have missed a decimal point. I think you mean 7.98 Euros a month.

twyntub

Agreed, but our gas bottle *always* runs out at the most inopportune moment. It's a law of physics knowns as "Sod's law".
800 watts is 0.8kW, so in an hour you consume 0.8kWh NOT 0.08kWh. Assuming 9c per kWh, cost per hour = 9 cents/kWh x 0.8kW x 1 hour = 7.2 cents - but that produces 3kWh of heat so specifically the cost is 7.2/3 = 2.4 cents per kWh...

798 euros? Divided by 26.6 cents suggest you have a 3000 day month!! I think you mean 7.98 euros...

Sounds spot on...

Solarwhizz

However the point I was making is that the efficiency and therefore the cost effectiveness overall is much better. IE, even though you consume at max 800W per hour, the unit cycles at a lower rate of consumption, and the exchange heat to where you need it is better giving overall better performance than most other forms of heat, and therefore cost effectiveness

twyntub

Well, yes... as the figures showed it costs roughly 2.4 (your figures) to 2.66 (my figures) cents for aircon to produce 1kW of heat for an hour vs 8 - 9 cents for conventional gas / electric heating to do the same. So it's three or more times cheaper.

There is an added complication... many modern Spanish homes are fitted with aircon which is massively undersized... this reduces the heating capability, but also reduces the CoP because because of the higher load. But it saves the builder a lot of cash, though...

Solarwhizz

Thats a relatively smalll problem compared tothe lack of power to run the units,
either local infrastructure not sized up, or Builders supply only due to legal mistakes(??). Supply underrated or just not available.

Maybe the time honoured log fire is probably best

twyntub

What?? Surely you're not saying that urbanisations in this area are built on the basis of back-handers paid to corrupt small-time local politicians without due regard to the sustainability of the development or the health / welfare of the people living there??

Well, that's what the EU think...