Solar water heating, how much??

tr3mor

Gorgeous_George wrote: »

Besides all the financial arguments for and against solar heating, has anyone considered the environmental impact of:

...

Of course they haven't. Do you honestly expect the British public to "consider" anything? They just do what they're told without thinking!

harryhound

Did we all listen to Radio4's "Moneybox" at the weekend ?

Because our government has decided to slash the subsidies for domestic electricity generation from 7K down to 2.5K; this was a good time to visit an early adopter. His kit installed over 10 years ago saved him 55GBP a year and he also benefited from a 45GBp off his electricity bill from EDF:rolleyes:
Electricity de France is selling to him at 10p/KWh and buying from him at 7p/KWh. Some suppliers will pay more BUT charge 100GBP for the export meter.
In Germany it seems the power companies are forced to pay something approaching 40p for the exported current. This will be one of the factors explaining why Britain has 5K exporting micro generators when Germany has 300K.

Meanwhile EDF, in its home territory, is pushing Ground Source Heat Pumps, with a big insulated floor slab, the householder creates a multiplier effect and a night storage heater. You cannot turn off an atomic power station, so it is in the interests of EDF to encourage people to pump heat out of their garden and into their floor slab, during the night, when it is damned cold anyway. In theory they get 4 units of heat for 1 unit of electricity.

Here in the UK we have the worst of all worlds: Big power stations stuck out in the country, probably burning high carbon coal dust, chucking away 2/3rds of the energy up those "steaming" cooling towers while putting the other 1/3rd through a turbine and into the national grid. This is the fools paradise of a country that used to have cheap coal and then plentiful oil & gas. As well as short term economics, our energy system is the product of government structures. The electricity board generated electricity, just as the ministry of "transport" built roads - the localised decision making that could create an integrated heat & power and an integrated transport system, was something that funny foreigners did.
[It wasn't always like that, Battersea power station, that huge roofless structure with a giant chimney at each of its four corners, was built to deliver its waste heat to the local population and dump the rest in the river Thames?!]

Where we go from here, I'm not sure - most people won't care as long as the lights stay on.

Harry.

trisontana

kisk wrote: »

I think we would have trouble keeping up with the French as France is the world's largest net exporter of electricity with gains of over 3 billion per year (euros). They help the Italians out as their demand outstrips production. Lots of homes in France are all electric due to cheap electricity derived from nuclear power stations.

If you click on this link :-

http://www.nationalgrid.com/uk/Electricity/Data/Realtime/Demand/Demand60.htm

It will give a real-time graph of the amount of electricity being used in the UK. On the right-hand-side you can see how much electricity is being imported from France.

Cardew

trisontana wrote: »

If you click on this link :-

http://www.nationalgrid.com/uk/Electricity/Data/Realtime/Demand/Demand60.htm

It will give a real-time graph of the amount of electricity being used in the UK. On the right-hand-side you can see how much electricity is being imported from France.

Thanks - Interesting.

My TV was on standby so I switched it off and didn't notice any change;)

Jazzy_B

I posted this in another thread, but I've had no response. Just wondered if anyone might be able to help.I live in a rural area of Scotland,without mains gas.
We are seriously thinking of solar water heating, as we can get a grant of 30% from SCHRI,and £950 from council. The grant from the council includes free top up loft insulation (we had quotes for this recently from £650 to £700 or £400 diy).
We've had quotes from 3 relatively local firms, from £3200 to £4000. Two of them said that they wouldn't have to price in bed and breakfast and travelling costs, so our quotes would be good.
We would end up paying £1300 ish, including the loft insulation
From reading all the threads about solar heating, I wondered if it would be worth getting some quotes from the registered English firms, or are they likely to be much dearer because of their travelling costs.
Has anybody bothered doing this, and found big variations in the quotes?

Fred_Bear_2

At 3.45pm France to GB is shown as -666MW. Does this mean that GB is exporting to France?

trisontana

Fred_Bear wrote: »

At 3.45pm France to GB is shown as -666MW. Does this mean that GB is exporting to France?

I think so, as it is labelled "France to Great Britain". It seems suddenly to have got warm this afternoon. I imagine the grid experienced a drop in demand and for the short term exported the surplus to France until the generating plants could lower their output.

jonnyw_2

If our water heating is oil, and we have 2 showers a day at 5 mins each plus 2 baths a week at about ten gallons of hot water and 5 machine washes a week at 40 degrees plus 2 washing ups in sink (not dishwasher) a day.

What sort of amount would that cost?

If you are spending your own money, not borrowed, and if it suppiled half your hot water a year and cost £3000, it would stack up if your total water heating was about £240 or more a year.

You would need a 50%+ grant for it to stack up if your hot water was costing as much as £120 a year. Is that right?

Weve got our house well insulated now with low energy lightbulbs and appliances.

My own view is that we would be better off investing in thermal underwear, however unglamerous and turning the central heating off a couple of weeks earlier and turning it on a couple of weeks later.

Cardew

jonnyw wrote: »

If our water heating is oil, and we have 2 showers a day at 5 mins each plus 2 baths a week at about ten gallons of hot water and 5 machine washes a week at 40 degrees plus 2 washing ups in sink (not dishwasher) a day.

What sort of amount would that cost?

If you are spending your own money, not borrowed, and if it suppiled half your hot water a year and cost £3000, it would stack up if your total water heating was about £240 or more a year.

You would need a 50%+ grant for it to stack up if your hot water was costing as much as £120 a year. Is that right?

Weve got our house well insulated now with low energy lightbulbs and appliances.

My own view is that we would be better off investing in thermal underwear, however unglamerous and turning the central heating off a couple of weeks earlier and turning it on a couple of weeks later.

It is very difficult to estimate how much oil is used for heating hot water. Those of us with gas CH(and no other gas use) can simply look at our meter in the summer(when CH is off) and work it out. Your usage seems to about average IMO. The average is about 5,000kWh a year to heat water.

The price for heating oil varies from day to day, but at current prices it works out at approx 3p for a kWh. Like gas boilers it then depends on the efficiency of your boiler.

However in general terms Oil is 30% or so more expensive than Gas for heating. I would have thought that your spend with oil could be in the region of £170pa

You can read the posts above and in other threads to get an indication on how much you would save. If you take the systems in the DTI trial as a baseline you will save approx 1,200kWh per year.

jonnyw_2

Well I work out on your figures that even on double the DTI figures I would have to get a system big enough for our useage costing £1200 (net of any grants). On the DTI figures themselves it would have to be £600.

Otherwise i would be better off putting the money in a mini cash isa at 6%and use the interest to pay for the oil.

When the price of the systems come down, the price of the oil goes up or interest rates go down so it stacks up, I will get one.