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

John_Pierpoint

grahamc2003 wrote: »

If yours takes 50s to generate 1wh, the average power over that time is 60x60/50, which is 72W. I take it you're not in Essex then?

What is the most Essex part of Essex?

Perhaps I live in the kernel of Essex.

Actually Essexness grades out, as you travel North North/East, towards Cambridgeshire and Suffolk. The Post Office gets a lot of stick for transferring villages into an Essex post code - Almost as bad as some parts of London, where one side of the street can be worth £ 000's more than the other.





Any prizes for working out where these villages are?

Hint - the second more difficult one thinks it is in Cambridgeshire.

anitainjune wrote: »

Thank you what you say sounds logical and I'm grateful its in plain English.

I am now very aware that the evening is now my most expensive time of day for consuming electricity and find myself looking round trying to spot what is increasing the red flash rate.

DW is going to go nuts about my new obsession.

Martyn1981

John, I've got a worrying image of you at 2.43am sitting impatiently in front of the TGM, like a 5yr old on Xmas Eve, waiting for the first flash of the day!

Don't worry, it'll wear off in, oh 10 years or so?

And yet another Essex bod, for me to look on with jealousy and envy. Don't worry, come the revolution, it'll all be different. And I'll be manning one of the Severn Bridges to keep our valleys, women and sheep safe from the invading hordes!

Mart.

pwllbwdr

Hi everyone. Install went up last week - minor hitch with the electrics so not gone live yet. Unlike some on this thread I'm without mains gas, so my comparisons are with oil.

One thing I'm considering is converting our AGA to electricity. The conversions run off a 13A supply, so not the economy 7 thermal store ones.

According to my calculations, on oil the thing costs on average £24.80 per week at 60 ppl. On electricity, the consumption is said to be about 220 kWh, so about £26.40 per week at our current tarriff.

Leaving aside the cost of the conversion, which is not small, it seems to me that it is likely to be worth it switching to electricity. On full day rate electricity the cost is only a little more than oil. For each day when a significant proportion of that can be supplied by the PV, there will be an accumulative saving.

As I see it the main consideration is the cost of the conversion, and I need to weigh this against the advantage of greatly reducing my oil use and thus my exposure to greatly fluctuating but seemingly ever increasing costs.

Does this make sense?

albyota

pwllbwdr wrote: »

Hi everyone. Install went up last week - minor hitch with the electrics so not gone live yet. Unlike some on this thread I'm without mains gas, so my comparisons are with oil.

One thing I'm considering is converting our AGA to electricity. The conversions run off a 13A supply, so not the economy 7 thermal store ones.

According to my calculations, on oil the thing costs on average £24.80 per week at 60 ppl. On electricity, the consumption is said to be about 220 kWh, so about £26.40 per week at our current tarriff.

Leaving aside the cost of the conversion, which is not small, it seems to me that it is likely to be worth it switching to electricity. On full day rate electricity the cost is only a little more than oil. For each day when a significant proportion of that can be supplied by the PV, there will be an accumulative saving.

As I see it the main consideration is the cost of the conversion, and I need to weigh this against the advantage of greatly reducing my oil use and thus my exposure to greatly fluctuating but seemingly ever increasing costs.

Does this make sense?

No, get a heat pump instead :eek:

John_Pierpoint

pwllbwdr wrote: »

One thing I'm considering is converting our AGA to electricity. The conversions run off a 13A supply.

Does this make sense?

My initial reaction is that you would blow the fuse if it were 13A.

My bog standard 4 ring job is on a 30 amp fuse.

[Mind you most of Hong Kong is on induction technology now as I understand - the heat is created in the pot rather than to heat the kitchen]

John_Pierpoint

grahamc2003 wrote: »

What struck me John is that we both must have got commissioned on the same day Tues this week?

Valentine's day - some how DW does not understand that this is much more exciting than red roses.

Martyn1981 wrote: »

John, I've got a worrying image of you at 2.43am sitting impatiently in front of the TGM, like a 5yr old on Xmas Eve, waiting for the first flash of the day!

Don't worry, it'll wear off in, oh 10 years or so?

And yet another Essex bod, for me to look on with jealousy and envy. Don't worry, come the revolution, it'll all be different. And I'll be manning one of the Severn Bridges to keep our valleys, women and sheep safe from the invading hordes!

Mart.

I've not yet managed to catch the moment when the inverter turns on and off. It turns ot 100% of a voltage that I don't know and turns off when that voltage drops by 30%.

I'm flashing at one per 3 - 4 seconds at the moment.

keep our valleys, women and sheep safe from the invading hordes!

Run boys you don't want to get the ugly one.

Seriously though do you get the Scottish "white settler" effect, or does that require romantic off shore island and crofter legislation?

A Technical Question

I have this manual that, as well as being 95% written in a foreign language, also tries to cover 7 different models including some that appear to be 3 phase.

Now sooner or later I am going to have a power cut, a short/fuse (or perhaps need to turn off to make repairs to my electrical system).
I don't think waiting until it gets dark will be an option.

Now the manual helpfully explains how to turn on - depending on what type of inverter is installed. Here in the UK it is pretty obvious that we have to be fitted with rotating double pole switches on both the PV strings and the AC connection to the grid (regardless of what might be incorporated in/on the inverter?)
The manual helpfully talks about "closing" the external switches.
to turn on, (Then a "traffic light" array of LED's will explain what is happening (preferably leading to a constant green !)).
The turning off instructions are to reverse the switching on instructions!!
BUT I've got three such isolation switches.

So in which order do I turn them on/off ?
Does it matter if the panels are bathing in full sunshine with nowhere for the electricity to go ?

Martyn1981

John_Pierpoint wrote: »

Valentine's day - some how DW does not understand that this is much more exciting than red roses.

I don't think waiting until it gets dark will be an option.

Now the manual helpfully explains how to turn on - depending on what type of inverter is installed. Here in the UK it is pretty obvious that we have to be fitted with rotating double pole switches on both the PV strings and the AC connection to the grid (regardless of what might be incorporated in/on the inverter?)
The manual helpfully talks about "closing" the external switches.
to turn on, (Then a "traffic light" array of LED's will explain what is happening (preferably leading to a constant green !)).
The turning off instructions are to reverse the switching on instructions!!
BUT I've got three such isolation switches.

So in which order do I turn them on/off ?
Does it matter if the panels are bathing in full sunshine with nowhere for the electricity to go ?

John, I've got 5 isolators, one on the AC between the TGM and the main consumer unit. Then one on the AC and one on the DC side of both inverters. They have stickers that carry pretty rock solid instructions - for me!

"Do not disconnect DC plugs and sockets under load - Turn off AC supply first"

Do you have any such rule, stickers etc?

On other forums, I've read people who actually understand this stuff (unlike me) who seem less worried about AC or DC first. But, I'll follow the instructions, just in case.

We had some months ago a flash power cut during those really bad winds and storms. The house electrics made the tiniest movement. Later I found that one inverter was reporting a fault. As I have 2, they are wired first into a small CU (acting as a Y junction) before the TGM. The RCD for the 'faulty' inverter had tripped.

I followed the instructions, switched off it's AC, then its DC. Flicked the RCD back up, and then DC then AC. It restarted fine. Probably could have just flicked the RCD up, but thought it worth testing the full procedures. No probs.

Regarding, bathing in sunshine, nowhere to go. If the house power is cut, the inverters will stop allowing power out - otherwise they could fry a workman, up the pole outside. So they can operate as such. So unfortunately, during a power cut, PV'ers are dead in the water too. Apart from Albyota, he'll have a bit squirrelled away!

Mart.

PS Tell the wife she gets a nice bunch of flowers each time a FIT payment arrives. She'll love the PV more than you (two ways to read that) in 2 seconds flat! M.

Martyn1981

pwllbwdr wrote: »

Hi everyone. Install went up last week - minor hitch with the electrics so not gone live yet. Unlike some on this thread I'm without mains gas, so my comparisons are with oil.

One thing I'm considering is converting our AGA to electricity. The conversions run off a 13A supply, so not the economy 7 thermal store ones.

According to my calculations, on oil the thing costs on average £24.80 per week at 60 ppl. On electricity, the consumption is said to be about 220 kWh, so about £26.40 per week at our current tarriff.

Leaving aside the cost of the conversion, which is not small, it seems to me that it is likely to be worth it switching to electricity. On full day rate electricity the cost is only a little more than oil. For each day when a significant proportion of that can be supplied by the PV, there will be an accumulative saving.

As I see it the main consideration is the cost of the conversion, and I need to weigh this against the advantage of greatly reducing my oil use and thus my exposure to greatly fluctuating but seemingly ever increasing costs.

Does this make sense?

Simply as a throw away view from a casual onlooker, if you've got those 2 amounts right (oil and leccy), then it looks good. But....

1. Given that you've already got the infrastructure in place, is there any chance that the oil price will go back down in the long term (ok stop laughing at me, but I had to point it out)? The numbers look close enough together to make electric a goer, but could imported electric price rises outstrip oil, I'm playing Devil's Advocate here?

2. Is an enormous percentage of that consumption in the winter and/or in the dark hours?

3. I assume that when the heating is on, during daylight hours, then you'd be consuming 100% of generation. What size system do you have, and what roof angle - steep (wintery) or shallow (summery)?

4. Are there additional benefits from not needing the oil side of things, less hassle, theft, free space, standing charges etc?

Any use/help?

Mart.

pwllbwdr

Martyn1981 wrote: »

Simply as a throw away view from a casual onlooker, if you've got those 2 amounts right (oil and leccy), then it looks good. But....

1. Given that you've already got the infrastructure in place, is there any chance that the oil price will go back down in the long term (ok stop laughing at me, but I had to point it out)? The numbers look close enough together to make electric a goer, but could imported electric price rises outstrip oil, I'm playing Devil's Advocate here?

2. Is an enormous percentage of that consumption in the winter and/or in the dark hours?

3. I assume that when the heating is on, during daylight hours, then you'd be consuming 100% of generation. What size system do you have, and what roof angle - steep (wintery) or shallow (summery)?

4. Are there additional benefits from not needing the oil side of things, less hassle, theft, free space, standing charges etc?

Any use/help?

Mart.

Thanks. Our system is 3.95kWp, we're in North Wales. It is SW facing, abt 35 degrees elevation. I reckon in summer it will come on stream quite early in the morning.

Oil hasn't dropped much in the last couple of years. Although the dollar oil price came down, the weak pound means that heating oil costs are still massive.

Consumption will undoubtedly vary from season to season, but a lot of the heat loss occurs when cooking is taking place, so consumption in summer daytime is still pretty high, especially if you set a timer to turn it down or off during the night.

I don't think anyone has made a heat pump AGA yet, but for the other question above, yes they do run off a standard 13A spur. They're continually on.

Martyn1981

pwllbwdr wrote: »

Thanks. Our system is 3.95kWp, we're in North Wales. It is SW facing, abt 35 degrees elevation. I reckon in summer it will come on stream quite early in the morning.

Oil hasn't dropped much in the last couple of years. Although the dollar oil price came down, the weak pound means that heating oil costs are still massive.

Consumption will undoubtedly vary from season to season, but a lot of the heat loss occurs when cooking is taking place, so consumption in summer daytime is still pretty high, especially if you set a timer to turn it down or off during the night.

I don't think anyone has made a heat pump AGA yet, but for the other question above, yes they do run off a standard 13A spur. They're continually on.

Evening. I'm hoping someone will point out a negative, as I'm worried that I may be missing something. But if not, then your idea (if the conversion isn't eye watering) sounds good. Also sounds like an ideal way to maximise the use of your generation. In fact, it sounds like maximising use is being taken out of your hands and become automatic.

Ran your rough details through here

http://re.jrc.ec.europa.eu/pvgis/apps4/pvest.php#

Changed the losses to 10%, might be cheating, but most people seem to beating the results, so as an optimistic figure, here's the results. The table is a little distorted, read column Em.

Fixed system: inclination=35°, orientation=45°
Month Ed Em Hd Hm
Jan 3.02 93.5 0.93 28.8
Feb 5.43 152 1.69 47.2
Mar 8.20 254 2.62 81.1
Apr 12.30 369 4.03 121
May 15.20 471 5.09 158
Jun 14.40 433 4.90 147
Jul 14.50 448 4.93 153
Aug 12.10 376 4.10 127
Sep 9.71 291 3.21 96.2
Oct 6.27 194 2.02 62.5
Nov 3.58 107 1.11 33.4
Dec 2.16 66.8 0.67 20.6
Yearly average 8.93 272 2.95 89.6
Total for year 3260 1080

3,260kWh's not bad. Had to pick a location so I plonked you in the middle of Gwydyr Forest Park (Why not, something for you to look at!).

Again, worried that I'll mislead you, but if no mains gas, rising oil prices (and thefts?), and a pretty decent PV system. I can't see a problem. Think we need someone to post a negative to get some balance.

Best of luck.

Mart.