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

old_grouser

The best practical way to store surplus energy - in the sense of being able to utilise it when the sun isn't shining - is as hot water, it seems to me. Unlike submarine batteries (or whatever) most people have most of the technology for this already in their homes. The problems are (1) finding and fitting a lower than normal wattage immersion heater and/or (2) creating a low-cost diversion device to switch surplus power to water heating. (1) is easy, though standard size low wattage immersion heaters are more expensive than they ought to be.There are people working on problem (2), but one day someone will devise and market something that does the whole job, no doubt...

albyota

old_grouser wrote: »

There are people working on problem (2), but one day someone will devise and market something that does the whole job, no doubt...

What like this?

http://www.sma.de/en/products/monitoring-systems/sunny-home-manager.html

nr16apple

old_grouser wrote: »

.... The problems are (1) finding and fitting a lower than normal wattage immersion heater ...... (1) is easy, though standard size low wattage immersion heaters are more expensive than they ought to be.

Thanks, 'Old Grouser', for telling us that 'finding and fitting a lower than normal wattage immersion heater' ... 'is easy', but I've searched high and low all over the internet for something like a 1.5kW 27 inch model (standard fitting) with thermostat without success. Can any one point to a source?

albyota

http://www.asap-supplies.com/marine/immersion-heaters/hotpot-immersion-heaters

old_grouser

There are plenty of low wattage immersion heaters for boats - but typically they are short, so only heat the top of a domestic tank. I believe you can get a full length 1kW element at http://www.surecal.co.uk/Product/ImmersionHeaters.aspx
or you can have one made to your specification by a number of firms. My point was only that they are much more expensive than the standard 3kW product, probably because there is less demand.

old_grouser

I have a lot of time for SMA technology - their Optitrac Global Peak has completely eliminated my early morning shading problem. However, I have heard that their new home management device will cost something of the order of £1000, whereas I have also heard that a good electrician can spatchcock something that does the same job for an immersion heater for about £40. One day there will be a simple and relatively cheap device commercially available to do just that. It's all about cost effectiveness...

John_Pierpoint

old_grouser wrote: »

I have also heard that a good electrician can spatchcock something that does the same job for an immersion heater for about £40.

I thought it was something to do with grilling chicken;)
http://www.youtube.com/watch?v=YID8CVXJ_BI&feature=related

jackieblack

A little update for anyone who's interested...
Went on holiday in the last week of July so 'end of month' figures for July (and consequently August) are estimated based on (mean) average generation over the 25 days we were away.

July - 268 kWh, 107% of prediction
August - 245kWk, 105% of prediction
September - 243kWh, 137% of prediction!:j

Cumulatively, to end Sept, 2202kWh generated, 120% of prediction :j

Our system was installed on 23rd October 2010 so looking forward to getting some 'end of year' figures in the next few weeks.
If we generate the predicted kWh in October we will have generated 86% of the kWh we used in the 12 months prior to installation. :j

Doc_N

jackieblack wrote: »

A little update for anyone who's interested...
Went on holiday in the last week of July so 'end of month' figures for July (and consequently August) are estimated based on (mean) average generation over the 25 days we were away.

July - 268 kWh, 107% of prediction
August - 245kWk, 105% of prediction
September - 243kWh, 137% of prediction!:j

Cumulatively, to end Sept, 2202kWh generated, 120% of prediction :j

Our system was installed on 23rd October 2010 so looking forward to getting some 'end of year' figures in the next few weeks.
If we generate the predicted kWh in October we will have generated 86% of the kWh we used in the 12 months prior to installation. :j

Excellent results, Jackie. Rather better than ours, bearing in mind the difference between system sizes (2.22/3.96) - I'm guessing you're a bit further south and east than we are.

For comparison, if it's of interest, our 3.96 kWp system produced 3660 kWh in its first year, roughly 10% ahead of the 3300 kWh installer projections.

Our electricity usage over the year dropped by around 1900 kWh, suggesting we used around 50% of what we generated.

Estimated break-even point around the 8 year mark, I'd guess.

keith_r59

I too am coming up to the first anniversary of my system this Friday. It's a very small system - only 1.32 kWp - and has so far produced 1326 kWh which is 32.6% above the installer's 1000 kWh projection. It will be interesting to see whether we have the same above average sunshine for the next twelve months which we have experienced this year.