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

ChrisJD

Bobbytee wrote: »

I have a monitor that was provided free by British Gas a few years ago, do you think that will do the job?

Simple monitors are limited in their abilities, and some cannot tell which direction current is flowing, simply showing its magnitude. This is no help if you need to know whether or not you are exporting power.

If you really want to see what is going on, you need to be able to monitor both the generated and used power. To do this, not only do you need a better monitor, but more detectors.

I have an EcoEye Smart PV, which works pretty well. There is lots of information on their web site, including downloads of instructions.

http://www.eco-eye.com/products-smartPV.html

Other products are available.

Chris

Doc_N

ChrisJD wrote: »

I have an EcoEye Smart PV, which works pretty well. There is lots of information on their web site, including downloads of instructions.

http://www.eco-eye.com/products-smartPV.html

Other products are available.

Chris

Thanks - worth a look. Here's an Amazon link, with some pretty positive reviews.

http://www.amazon.co.uk/Eco-SMART-PV-Energy-Monitor/dp/B008NMDI1U/

pvnubie

I have an eco eye smart pv, been using it for 6 months.
For me it works really well - mine is connected to my Linux satellite receiver via usb and takes the readings every 5 mins and uploads them to a website called pvoutput.org. Very versatile unit, however I found the software that comes with it
to be hit and miss when reading the data off the memory card, often losing the data.

I too am looking at how best to utilise my excess power, currently got 3.3kw system with 75% being exported.
I looked at dumping this into my hot water but it didn't make m much sense to me.
If I have 2000 kwh dumped into dhw every year I would lose 2000 x5.5p export, £110, using oil for my dhw at 7 per kwh would cost me £140 per year so I reckon my savings would be a pitiful £30 per year, at a cost including installing of £300, it would take 10 years to break even!

On lots of things I've read many off them don't take the lost export into account, which is fine if you don't get paid for it but makes a big difference if you do.

My latest thoughts are to run a low (300ish) wattage dehumidifier as a clothes dryer, on a timer to run at peak times or programmed to come on when generation is suitably above usage.

Has anyone else tried this or got any thoughts or advice?

theboylard

pvnubie wrote: »

If I have 2000 kwh dumped into dhw every year I would lose 2000 x5.5p export, £110, using oil for my dhw at 7 per kwh would cost me £140 per year so I reckon my savings would be a pitiful £30 per year, at a cost including installing of £300, it would take 10 years to break even!

Not sure you fully understand how the FiT, export and diverters work?

You get paid for every kWh you generate. This is recorded on your export meter, from which you report quarterly readings to your FiT provider and receive a payment upto 8 ish weeks later, depending on who you are with.
From that reading, you are also paid for 50% of the reported generation figure at your export rate of 5.5p. This assumed export, or deeming as it's actually termed, is paid regardless of whether you export it or not.
This is why diverters are quite popular amongst pv owners, it's maximising the use of the energy generated, but doesn't affect the payment for generating.
In my case it cuts down my gas usage as I'm getting free hot water.
My gas/leccy bills went from £135/month to an average of £48 during the summer.

Martyn1981

pvnubie wrote: »

On lots of things I've read many off them don't take the lost export into account, which is fine if you don't get paid for it but makes a big difference if you do.

Hiya pvnubie and welcome.

Can I ask, do you have an export meter, and a deal/contract with a leccy company for said export?

I only ask as your post suggests you have a meter(?) and you refer to 5.5p export rather than the standard 4.77p (for installs since 1/8/12).

I've heard of people fitting an export meter out of interest, but not of anyone (with a normal domestic system) having one and being able to find a company willing to contract for such small(ish) amounts of export.

Actually, scrap that, I think I read years ago that some companies will contract for small export, but the annual charge of perhaps £30 or so, makes it less attractive.

I'd appreciate any info, if you have it.

If you don't have metered export, then as theboylard states, export is simply deemed (and paid) at 50% of generation, regardless of actual export. I get paid for 50% despite exporting ~70% of generation.

Mart.

pvnubie

Sorry my post was a bit scant with details.
I'm from NI, which I believe has a different system to the rest of the UK.

I have a generation meter which i get paid 16.9 p for each unit generated regardless of usage/export.
I also have an import/export meter and for every unit I export I get paid 5.5p from Power NI who I have an export contact with. I think the way it works is they take over my NIROCS and then pay me for my exported electricity.

For those not getting paid based on actual export i guess using rather than exporting is more beneficial, this may be more the normal setup which is why I've seen few posts taking account of export income.

For me i consider my excess leccy to be cheap leccy at 5.5p rather than the 17p that I would pay if I had to import it, but I still want to make good use of it

Using it to heat my dhw costs me more than using my oil, with oil at a very low price of 34p a litre, it actual works out about 4p per kwh, my first post stated 7p as that would be closer to the norm over the past few years with oil being 60p per litre, but we can't depend on it staying this low for long....

Martyn1981

Thanks pvnubie, that makes sense, I didn't realise the export was metered in NI, I wish mine was in Cardiff.

So you get 16.9p for generation + 5.5p for export, compared to 13.88p (soon to be 13.39p) + 4.77p. Not bad, but how do costs work out in NI, is it more? On these threads over the last 6 months we've seen lots of quotes under £6k (for a 4kWp system), many in the mid to low £5k's and the occasional one dipping under £5k recently.

Mart.

pvnubie

Martyn1981 wrote: »

Thanks pvnubie, that makes sense, I didn't realise the export was metered in NI, I wish mine was in Cardiff.

So you get 16.9p for generation + 5.5p for export, compared to 13.88p (soon to be 13.39p) + 4.77p. Not bad, but how do costs work out in NI, is it more? On these threads over the last 6 months we've seen lots of quotes under £6k (for a 4kWp system), many in the mid to low £5k's and the occasional one dipping under £5k recently.

Mart.

Hi Mart, my 3.3kwp was just over £5k which should give me a payback of about 7 years at best guesstimate, based on exporting 75%. If I can make better use of the excess then this would reduce slightly so I think I got a reasonably good deal.

The eco eye monitor was an extra £85 which was an afterthought really as having both a generation and an export meter i thought i wouldn't need any other monitor. But having the eco eye gives you the extra ability to see detailed generation and usage, real time and over time to a very accurate degree, which allows you to analyse it to death!
Add a wifi plug and a bit of programming and i have now got a cheap 'diverter', all I need now is something useful to plug in lol!

old_grouser

Hi PV..
...and welcome to the club!
Times change. My 3.3kWp system was installed in 2011, earns me about three times what yours does, but cost more than £13k. Oscargrouch has a neat formula for comparing the performance of different-sized systems. My neat formula for comparing the performance of different priced/different return systems is the familiar ROCE - return on capital employed. Ignoring the benefits of free electricity usage (which don't apply to your NI set-up) the annual cash return from my system divided by the original cost (times 100 to make it a percentage) comes out at 14% (and more like 18% when free usage is included). Where else can you get a 14% net inflation-proofed return?
With a bit of ingenuity you can work out how to calculate the equivalent annual return on the basis of your daily output - and watch the percentage rise as the days lengthen! This is a cheering thought...


Old Grouser

1961Nick

old_grouser wrote: »

Hi PV..
...and welcome to the club!
Times change. My 3.3kWp system was installed in 2011, earns me about three times what yours does, but cost more than £13k. Oscargrouch has a neat formula for comparing the performance of different-sized systems. My neat formula for comparing the performance of different priced/different return systems is the familiar ROCE - return on capital employed. Ignoring the benefits of free electricity usage (which don't apply to your NI set-up) the annual cash return from my system divided by the original cost (times 100 to make it a percentage) comes out at 14% (and more like 18% when free usage is included). Where else can you get a 14% net inflation-proofed return?
With a bit of ingenuity you can work out how to calculate the equivalent annual return on the basis of your daily output - and watch the percentage rise as the days lengthen! This is a cheering thought...


Old Grouser

Agreed.....if you were selling annuities that returned 18% for 20 years & 4% thereafter, they'd be biting your hand off.