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

orrery

Doc_N wrote: »

Since we're talking lamps, am I alone in being just a little wary of converting to LED just yet?

Looking at the LED lamps we've bought in the last few months, I'd say that they've just about started to mature - my first LED lamps (GU10) were very blue and poor, but the more recent ones are very good.

I can't see a justification for swapping CFL for LED, until they pop but the halogen GU10 are awful. My daughter has about 20 in her kitchen - about 0.5kW, so we've swapped them for 5W LED, which are brighter and only take 100W.

We've relegated the old halogen bulbs to the bathrooms, where (at this time of year) the heat generated is welcome.

Where LEDs have been struggling is with the standard large bulb, but I've managed to get a 15W globe recently which replaces a 20W CFL, not much of a saving but they are 'instant on'.

orrery

Martyn1981 wrote: »

@ orrery, not having a go, but I've always disliked that McKay quote. It seems to assume that doing small things prevents doing large things. Whereas I'd hope small simple gains are a good way to show people what can be done and build up interest and momentum in doing more.

I completely agree, but even the media seems to focus on this 'unplug your phone charger' nonsense. It is important that people lift their sights a little.

pinnks

I would agree with the comments about the early LEDs. We put some 12V 4W halogen replacements in our living room and kitchen but the light always looked somehow floury or dusty and for my eye, and despite being warm white 3000K or so seemed to have a greenish tint.

I also had 4 x 14W CFL in the bathroom which take a while to warm up. Decided to change them for some 3W long-body GU10 LEDs from TP24 and for me the warm white and light quality are excellent. Decided to invest in replacing those floury ones with the same bulbs but 12V MR16 3.5W again form TP24. Only trouble with their MR16s is that they don't survive a 5m fall from the light up in the cathedral ceiling:eek: Still better to let go of the bulb than the ladder:T

Also found some good 1.5W and 3W capsules at 40p and 70p each. Impressed with those too.

So, is it time for LEDs? In my view yes but not if it is only to replace non-kaput CFLs - just wait for them to die and then go LED.

And the prices are dropping rapidly. I paid £12 for my first 12V MR16 LED. The new ones are "only" £4, so as long as they last a few years (kitchen and living room lights were 180W halogen and now 18W), and there is no reason to think they won't, then the investment will repay itself.

Interesting isn't it, we never talk about the investment return of a tungsten or CFL bulb:rotfl:

cdunne

Thanks for the reply to my question Orrery. Today I've found viridian Pod which does claim to work with PV and combi boilers and is the sort of thing I was after but I suspect it also costs a lot.

Another thought is buy oil filled radiators and use these with one of the control systems. They seem quite cheap new 1500w unit I'm sure you can pick them up second hand. But would it be worth it in the winter?

Another thought is there a low wattage insulated water boiler that can be run on a controller? I've found this post that talks about insulating one but are such things commercially available? Edit I've just found Neostar Perma Therm 3.5 Litre for £69 on Amazon, this seems to do what I wanted (only 3L) and is only 680watts.

orrery

cdunne wrote: »

Another thought is buy oil filled radiators and use these with one of the control systems. They seem quite cheap new 1500w unit I'm sure you can pick them up second hand. But would it be worth it in the winter?

As a form of heating, no. I've got x2 small oil-filled rads to do that and it is waste of time.

I have the output from the SolarImmersion on x2 13amp sockets (primary and secondary outputs) so I can swap them over. The only use I've found is to put the rads on the primary channel for when we are away to give some sort of assistance to keep the house from freezing but that depends on there being low power usage in the rest of the house otherwise there isn't enough surplus to make any contribution.

If we are home, then I leave the immersion on the primary channel, but the contribution is very low at this time of year and never enough to heat the whole tank and switch over to supplying the rads.

The sort of measures you are considering will have a very marginal return and will be difficult (impossible?) to justify.

Martyn1981

cdunne wrote: »

Another thought is buy oil filled radiators and use these with one of the control systems. They seem quite cheap new 1500w unit I'm sure you can pick them up second hand. But would it be worth it in the winter?

Hiya, as orrery says, it might not be worth it in simple terms. However, what I've found is that when the house has heated up with GCH, or during the early spring, or mid autumn, when the house temp is marginal, I can use my oil rad to keep the chill of the room I'm in.

The heat gain is marginal, it runs at 400W but switches on and off every ten minutes, so around 200W/hr. My theory is that it's probably cheaper than running the GCH for a burst, as that will warm more of the house, and subsequently cool back down. So whilst the leccy costs more, I hopefully use far less than the equivalent gas.

If my theory is correct, then that takes away a lot of the mental strain of trying to match the extra 400W draw to excess PV generation. In total, on marginal days, say 100pa at 5hrs and 200W, that's probably about 100kWh's that gets used.

In reality of course there's also the fact that there's added heat as I'm in the room, possibly a telly and a cat, plus Fifi the GDP and some solar gain from the windows, so rationalising it is tricky, but it seems to work ....... on a very small scale.

Mart.

Cardew

orrery wrote: »

I completely agree, but even the media seems to focus on this 'unplug your phone charger' nonsense. It is important that people lift their sights a little.

Agreed.
Such is the widely spread misinformation on the subject, that posters in the gas/electricity forum complaining about high electricity bills invariably start their posts ' I always unplug phone chargers and turn the TV off at the wall'

pinnks

Going back to diverters and radiators, I have 2 x 2,400W oil rads on my immerSUN in addition to the immersion. As Martyn says, not a lot of use in winter but they certainly have a impact in those in-between months when the sun is out and about, you don't need to heat the bedrooms etc but it is a bit chilly downstairs.

I use 2 rads because I found a single rad will reach its own cut-off temp before the room itself is warm. Using 2 rads means that one is always on. We can lift the temperature of our living and dining rooms (broadly open plan) by about 2 or 3 degrees on a reasonable day, which keeps us going to bedtime. Pumping 8-10kWh into the rads in late September/October and in March/April is doable.

Payback for you would be the cost of 2 rads plus a bit of wire and some trailing sockets - perhaps £100 - as you already have the immerSUN but don't have a tank to heat with it...

cdunne

Short term am going to try the little water heater. My contract for FiT came through today. I'm with EON same as my supplier one thing I wondered from the initial form said they cover customers from other suppliers, is there a market with some energy companies paying higher rates so they can get their green targets up? I didn't realise that FiT rates have been announced from 1st Jan 2016, is it just thought that the scheme will be scrapped before then?

Martyn1981

cdunne wrote: »

I didn't realise that FiT rates have been announced from 1st Jan 2016, is it just thought that the scheme will be scrapped before then?

Hi. The announced figure for 1/1/16 of 12.03p/kWh is simply part of the current FiT programme. Basically, installs in the 3rd qtr were high enough to trigger a 3.5% reduction.

At the same time the government is consulting on its plans to cut domestic FiT rates for PV down to 1.63p. Effectively ending demand side installs, in line with their ending of support for large scale PV and on-shore wind too.

The consultation is taking longer than expected as they have to read/review all of the responses (50,000+ I think) and have received a lot of negative press both national and international.

Once they decide what they are going to do, they'll have to announce it and lay it in front of Parliament for 40 days. There are differing views as to how those 40 days might be calculated, calendar days, parliamentary session days etc.

The current rush to beat the deadline has been large (but not as big as some feared), so qtr 4 installs will probably cause a larger degression from 1/4/16 (3.5%, 7%, 14% or even 28%) assuming the current scheme is still running in April.

Mart.