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

shavy65

Iv got a Solic200 I think. I`m sure it came with a 10 year warranty as well. I don`t know the price though as I managed to get it as part of my solar panel deal. I find it saves my boiler firing very often, and definately recommend.
Another good tip is (if ur hot water tank has two stats as mine does) turn the immersion stat up higher than the tank stat, meaning the immersion heater could, technically, keep the tank temperature up without the boiler kicking in even when using hot water......when sunny and diverting obviously : D
I actually bought an adapter to fit a garden hose to my utility room tap last summer and used the `free` hot water for my familys paddling pool, great fun.

orrery

shavy65 wrote: »

Another good tip is (if ur hot water tank has two stats as mine does) turn the immersion stat up higher than the tank stat

I've turned the tank stat down to 45C, which is the minimum that will get us a bath and a shower. The boiler fires up for about 30 minutes max, 7am to 7.30am.

That way we always have enough hot water when we get up at 7.30am, but it should theoretically leave the water just about cold to maximise the solar contribution during the day.

* all the above subject to rounding error imposed by SWMBO, as she wouldn't stand for a cold bath, so the 45C setting is on the higher side.

*2 - I've re-done the pipework so that the pump over-runs after 7.30am and the bathroom rad and towel rail are outside of the two control valves, so they effectively purge the waste hear from the boiler into the bathroom.

zeupater

Dave_Fowler wrote: »

Two to three years payback period suggests he is saving £200 a year on hot water heating. He is either using a lot of hot water or he is heating it by expensive oil.

I normally would use gas to heat my hot water. Using the PV diverter I did not need to use any gas between mid May until well into October last year. During the winter months there was also a saving. I reckon I may have saved about £65 in the year.

Dave F

Hi All

Agree with the above ... our solar thermal setup probably displaces somewhere around 1625kWh/year of gas usage, so using a fuel cost of ~4p/kWh that's spot on at £65 ....

HTH
Z

irco

Doc_N wrote: »

Presumably these devices (Immersun etc) are coming down in price as they get more popular?

Any advice as to which are best, most reliable etc? And prices, including fitting?

I chose the Immersun based on personal recommendation and searching for reviews online. It seemed to be one of the best (but not the cheapest) for performance, reliability, robustness and build quality. It gives a readout of Kwh and monetary savings, daily, weekly, monthly, yearly and total since installation, each users tariff can be programmed into the unit. I have no first hand knowledge of any other unit so can only comment on the unit that I have.
The installation and user guide can be downloaded from the firms website which gives full installation details of the different configurations for the unit.
It has performed faultlessly since I had it installed, this is not intended to imply that other makes of units wont.

ChopperST

We've saved £50 since January this year which would seem to correlate with others usage.

I reckon the unit (Immersun II) will break even at best, however financial reasons wasn't the sole reason for installing. Having the means to reduce your usage of fossil fuels is rewarding in a moral sort of way as well IMHO.

orrery

ChopperST wrote: »

We've saved £50 since January this year which would seem to correlate with others usage.

I reckon the unit (Immersun II) will break even at best...

I've got a SolarImmersion unit which was £240, self installed. Of course, I bought reels of cable (including twisted pair data cable) to do the install, then I added a de-stratification pump (which has never worked properly, as it seems impossible to keep the air out) and more recently a longer immersion. So, the cost of the box itself isn't the whole story and I'm sure that I'll not ever get my money back on it all.

But - it works well, and from an environmental point of view, I'm happy I did it.

regards
Ian

ChopperST

We're lucky in that we are in a new build property with an unvented cylinder with an immersion. The immersion stopped working after a few weeks but we have a 5 year warranty with the house. The guy that came out explained that the immersion fitted to our cylinder is only for light use but was surprised it broke after a month (went open circuit).

He very kindly fitted an uprated immersion that they use in renewable installations and in flats where electric is the sole fuel source.

The other bonus is the immersion heats the water up to 80 degrees as opposed to the gas whose thermostat is limited to 65.

orrery

ChopperST wrote: »

The guy that came out explained that the immersion fitted to our cylinder is only for light use but was surprised it broke after a month (went open circuit).

He very kindly fitted an uprated immersion that they use in renewable installations and in flats where electric is the sole fuel source.

Interesting - that is what the tank manufacturer told me. When I spoke to the immersion manufacturer, they said they didn't understand what he was talking about.

ChopperST

The flaw in our original immersion was it had the Thermal cut out built into the body of the unit i.e. no dedicated thermostat. He explained that prolonged use of these units regularly resulted in the thermal cut out kicking in too early. He switched ours for a larger unit and added a dedicated rod style thermostat with a dedicated temperature control for the thermal cut out.

nigelpm

ChopperST wrote: »

Having the means to reduce your usage of fossil fuels is rewarding in a moral sort of way as well IMHO.

I think that's a pretty naff argument myself.

If you are thinking environmentally you'd still be better using gas to heat your water and have your neighbours(via the grid) make use of your surplus electricity.

It's clearly better for you but not the world as a whole.