So now I have a solar PV system how do I make the most of it???

cannonballdaze

Pound per kWh - how do you arive at his figure please ?

You and I both know that we are being paid in excess of one pound for every kWh that we actually export

EricMears

Cardew wrote: »

For people with metered water supply that might well be a false economy.

Perhaps I didn't make myself clear the first time. We weren't doing any extra washing or dishwashing - just bringing forward loads that we would have had to have done some time . e.g. OH likes to see her curtains washed occasionally - though I have managed to persuade her that they don't need doing every week. Far better to do them this week when there's plenty of free electricty than wait a few weeks and pick a dull day. Similarly, the oven shelves don't get washed every week but this is a good time to do them.

P.S. 'extra detergent' isn't really a problem - partly for same reason as above and partly because we're getting quite good results with 'eco-balls'.

EricMears

Kernel_Sanders wrote: »

You and I both know that we are being paid in excess of one pound for every kWh that we actually export

Afraid I know nothing of the sort ! We are being paid 45.4p for every Kwh we generate and that was always intended to be compensation for being early adopters of a technology that we're helping to make cheaper for others.

The payment for exporting is just 3.2p - and only then if you really do make use of 50% of everything generated; most people don't so are effectively getting 2p or less per Kwh exported. I think I'm probably using up to about two thirds of generation so arguably I'm being paid around 5p/Kwh which I make rather less than one pound ! you'd have consistently to use more than 95% of your own generation to be able to claim it was worth anything like a pound per unit exported.

There's nothing wrong with 'greed' ! If governments weren't messing about with interest rates, I'd probably be earning around 8% on my savings rather than the 3% I'm actually getting or the 1% the banks & building societies would be dropping that to if I didn't keep 'churning'. Using some of my savings to get a return approaching 15% on some of them goes some way to recovering what I'm losing. To a considerable extent, arranging one's finances for maximum economic gain will usually be 'greener' than not making the effort.

EricMears

Kernel_Sanders wrote: »

Every watt we use in this way means an extra watt (watts?) that will have to be generated from fossil fuels and conveyed (at some loss) to our neighbours.

I'm sure the same point has been made here before - and it was disputed then too.

I didn't install SPs to 'help my neighbours' and if I didn't export any electricity at all they would be no worse off than if I hadn't bothered; indeed, they'd still be benefiting' in that I'm not now buying as much electricity as I might so less needs to be generated elsewhere.

Kernel_Sanders

cannonballdaze wrote: »

Pound per kWh - how do you arrive at his figure please?

We are being paid 45.4p for every kWh we generate whether we use it or not, therefore average consumption of just 54.6% of generation (which I'm sure Eric and me exceed) would result in a payment of £1/kWh actually exported. Put more simply, if we were to use during this financial year ⅔ of our output, then the industry would have to pay us 3 x 45.4p for every kWh that it can resell.

Martyn1981

Kernel_Sanders wrote: »

We are being paid 45.4p for every kWh we generate whether we use it or not, therefore average consumption of just 54.6% of generation (which I'm sure Eric and me exceed) would result in a payment of £1/kWh actually exported. Put more simply, if we were to use during a year {{Fraction|2|3}} of our output, then the industry would have to pay us 3 x 45.4p in order to get a single kWh from us.

Please tell me that you haven't fallen for this 'maths trick'.

So you're saying that a person generating 4,000 units and using 1,000, sells 3,000 units @ 4,000 times 45.4p = 60.5p/unit

but somebody making more efficient use of their system and exporting only 10%, 400 units, sells them at 454p each.

The amount paid for generating the units is the same regardless of how large or small a number you divide it by. That payment is to finance / encourage the purchase.

The amount paid per exported unit is a deemed 3.2p (soon to be 4.5p for those installing after 1/8/12). Given that on average most PV systems are exporting more than 50%, then the actual payment per unit is a little less.

The 45.4p or 21p is highly relevant to the introduction, application and running of the FITs scheme, but is entirely irrelevant to the cost of any exported units.

Edit: Should have also pointed out that the domestic FIT schemes (PV, wind, hydro, CHP (did I get em all?)) are for micro-generation, use on site as demand reducers. They were never conceived as major suppliers.

Mart.

John_Pierpoint

If you like in a dense close knit community, I am sure it should be possible to arrange with your neighbours to use up your spare production at this time of year; would involve a lot of electrical instruction though and probably some risks. It reminds me of the "3 day week" when the little portable generator got plugged in all over the place to keep lighting and limited power circuits operating. Do much more convenient than resorting to car batteries.

John_Pierpoint

Cardew wrote: »

For people with metered water supply that might well be a false economy.

Severn Trent have one of the cheaper rates for water/sewerage at £2.44 per cubic metre. So 2.44 pence per 10 litres. South West Water rates are double at over £5 per cubic metre - so 5p per 10 litres/

According to WHICH, new washing machines use between 31 litres and 60 litres for an average load. Older machines use more - over 100 litres in some cases.

My washing machine as an example uses 0.4kWh or 0.6kWh on most cycles(rarely a a 0.9kWh cycle). Some 90% of that consumption is for heating @ 3kW.

Making the assumption that all the electricity can be provided from solar(covering the 3kW load) the saving per cycle would be typically 2p to 3p on E7 and 4p to 6p on daytime rates.

However the cost of water for an extra wash could be anything between 8p and 14p with a new machine in Severn Trent area; ranging to 50p in extreme cases for an old machine in the South West.

I don't know what the average might be across the UK - I would have thought 15p????

Then there is the question of extra washing powder!!

The same principle applies to Dishwashers - albeit the electricity savings are greater(provided you have a 'spare' 3kW) and the extra water costs are lower.

I have Bosh washing and dish washing machines that are a dozen years old - The bog standard design, not some "eco" version that uses yesterday's rinse water to start today's wash.

A standard clothes wash uses just less than 60 litres (it goes into a dustbin "donated" by a cannabis farmer;) and I water the garden with the waste water. Woollens and delicates get an extra rinse) typical electrical consumption, especially when using a modern 30 degree detergent is perhaps a bit over 1 kWh as the machine is on "cold fill", and spread over more than an hour it takes to do the wash.

The dish washer used roughly half the water (ie 30 litres) and I try to avoid it excessively "cooking" the crockery in an attempt to boil off all the wetness.

Fortunately what comes onto my land tends to stay here, so I don't pay the sewerage charge that would add more than 66% to my water bill.

The economy 7 rate I pay is a marginal 4.1p plus 5% tax.
The day rate is a marginal 10.82 p plus 5% tax
[I also pay a standing charge of 37.2p per day - must review this at the end of my contract]

So my marginal cost for a clothes wash is say roughly 8p for the electricity and 8p for the water - so doing the wash in the day time is saving me 8p for the wash and another 5p - 10p to dry it using the "low heat" setting.

The dish washer must be a little less.

These figures will never add up to a fortune.

KevinG

Martyn1981 wrote: »

The amount paid per exported unit is a deemed 3.2p (soon to be 4.5p for those installing after 1/8/12).

Ooh, I missed that, what's happening after 1st August? Have you got a link?

GaryMo_2

http://www.energysavingtrust.org.uk/Generate-your-own-energy/Financial-incentives/UK-Government-changes-to-Feed-in-Tariffs-new-and-proposed

http://www.ofgem.gov.uk/Pages/MoreInformation.aspx?docid=1&refer=Sustainability/Environment/fits/tariff-tables