Solar installation prices

[biffvernon]

I suppose there's a certain logic there Biff.
Many years ago I thought of building one in brick or more likely concrete and heating with wood in a similar manner to a Roman hypocauste but then when I really thought about it , the cost , the effort involved just to have a bath in the garden the idea was shelved under "what was I thinking?"

We have a bath in the garden. It's an old steel bath, cost zero, raised above a fire pit with flue-pipe to one side. It's fired by all the long, awkward shaped bit's of scrap wood that are more trouble than its worth to cut into wood-stove sized pieces, cost zero. Half buried in earth and with the embers glowing underneath, it keeps hot for hours, perfect if you want a long bath at no cost.

[PS_RalphW]

I've already posted this before. Friends, who are eco-friendly at heart, had grid tied solar panels installed, with the very high fit payments guaranteed for decades. The mother -in-law in the basement flat got a retirement lump sum and 'invested' it in a hot tub in the garden shed, heated daily by electricity. I calculated it took all the electricity generated by the panels, plus a bit, to heat the water each day.

The FIT payments will pay for the mother-in-law's bath for the next 20 years.

[kenneal - lagger]

But all that energy use is good for GDP and growth, Ralph!!

[Lurkalot]

I was aware of the FITs but until recently hadn't looked closely. It's been explained to us that it is broken up into a generation tariff set at £0.0439 and that is paid for every unit generated even if we use it ourselves. Additionally there is an export tariff at £0.0485 which until we all have smart meters is assumed to be 50% of what we would generate.
It was also explained that we could put panels on our rental property and collect the FITs and even if we sold the our house we are still entitled to those tariffs .
Ralph , I may just have to keep that one quiet .

[biffvernon]

Going down

http://electrek.co/2016/04/28/i-was-wro ... irt-cheap/

[kenneal - lagger]

..... It was also explained that we could put panels on our rental property and collect the FITs and even if we sold the our house we are still entitled to those tariffs .
Ralph , I may just have to keep that one quiet .

That would have to be written into the contract L and the purchaser's solicitor should pick it up. They would ask for a rental on the use of the roof and probably an insurance backed warranty that against any damage caused by your installation to them, their property and any third party. The purchaser's solicitor would probably recommend against the sale without transfer of ownership of the panels and the FIT.

[kenneal - lagger]

Going down

http://electrek.co/2016/04/28/i-was-wro ... irt-cheap/

This article makes the mistake of thinking that unlimited growth in supply is possible. Continually doubling the amount supplied affects the cost of supply of the raw materials eventually especially when you're using rare earth metals in the manufacture.

Unlimited growth in the supply of lithium for batteries for both cars and domestic storage could be difficult. Yes, there could be other storage methods developed but they will cost a lot initially and even they will come up against limitations.

We seem not to have learned anything, or some journalists haven't!

[PS_RalphW]

A friend who is an electrical engineer visited and encouraged me to have another go at setting up a small off grid PV system I failed to install about 8 years ago. I might as well set it up in an inefficient way as leave it doing nothing.

I have 2 180W 24V panels, a charge controller (12/24 V 30 amp max) and 2 110ah batteries (elecsol carbon fibre) and a 24V modified sinewave 600W inverter.

I have a flat roof to the west of the main house as the only possible place to put the panels, where they will be shaded until about noon. I will have to lay them nearly flat on the roof, as the house is listed and the panels must be easily removable and not visible from ground.

We set up the panels and tested the charge controller and batteries. The panels worked well when charging the batteries individually, 24V panel charging 12V battery, but struggled when charging the batteries in series (24 V charging 24V) The charge controller is rated at 24V and has a max input rating of 47V, so putting the panels in series could overload the charge controller, especially as the panels can reach 32V when not under load.

Also, I am planning to set the panels up to provide backup power to our oil central heating in the event of a power cut. (and power communications - wifi router and phones , lights etc)

I can isolate the central heating from the main ring circuit by replacing an isolation switch with a stand 13amp plug and socket.

I am not sure that the boiler controller and pump will work off modified sinewave, so I think I would be better buying a 12V pure sinewave inverter, and charging the batteries in parallel.

I will need to buy inline fuses for each of the batteries, and run wires etc through the attic.

The batteries are now over 5 years old, and were left uncharged for some years, so I do not know how much capacity they have left. I have charged them and they do appear to still be working well. (They are sealed liquid electrolyte batteries).

Will I have any problems running the batteries in parallel? Do I need to add any extra circuit components to protect one battery from the other if they discharge at different rates?

I'm hoping that the system will produce enough energy to power our central heating directly from PV in the summer months (we run it morning and evening to provide hot water. It needs about 400Wh a day).

In winter it will be an emergency backup supply.

[woodburner]

These people can help with your batteries, it's the nearest to truth I have found on the web. http://sterling-power.eu/support-faq-2.htm

[adam2]

A friend who is an electrical engineer visited and encouraged me to have another go at setting up a small off grid PV system I failed to install about 8 years ago. I might as well set it up in an inefficient way as leave it doing nothing.

I have 2 180W 24V panels, a charge controller (12/24 V 30 amp max) and 2 110ah batteries (elecsol carbon fibre) and a 24V modified sinewave 600W inverter.

I have a flat roof to the west of the main house as the only possible place to put the panels, where they will be shaded until about noon. I will have to lay them nearly flat on the roof, as the house is listed and the panels must be easily removable and not visible from ground.

We set up the panels and tested the charge controller and batteries. The panels worked well when charging the batteries individually, 24V panel charging 12V battery, but struggled when charging the batteries in series (24 V charging 24V) The charge controller is rated at 24V and has a max input rating of 47V, so putting the panels in series could overload the charge controller, especially as the panels can reach 32V when not under load.

Also, I am planning to set the panels up to provide backup power to our oil central heating in the event of a power cut. (and power communications - wifi router and phones , lights etc)

I can isolate the central heating from the main ring circuit by replacing an isolation switch with a stand 13amp plug and socket.

I am not sure that the boiler controller and pump will work off modified sinewave, so I think I would be better buying a 12V pure sinewave inverter, and charging the batteries in parallel.

I will need to buy inline fuses for each of the batteries, and run wires etc through the attic.

The batteries are now over 5 years old, and were left uncharged for some years, so I do not know how much capacity they have left. I have charged them and they do appear to still be working well. (They are sealed liquid electrolyte batteries).

Will I have any problems running the batteries in parallel? Do I need to add any extra circuit components to protect one battery from the other if they discharge at different rates?

I'm hoping that the system will produce enough energy to power our central heating directly from PV in the summer months (we run it morning and evening to provide hot water. It needs about 400Wh a day).

In winter it will be an emergency backup supply.

If the batteries have been left unused for several years then they may now be useless, worth a test but do not raise your hopes.
If you require a 12 volt system, then the batteries may be simply connected in parallel, provided that they are the same type and age.

If in doubt as to the voltage of a PV module, then it can be worth counting the number of cells, each one contributes about 0.5 volts.
A module intended for charging a 12 volt battery would normally have 35 or 36 cells to give about 17/18 volts under load. That allows for a battery voltage of about 14.5 volts under full charge, plus 1 volt loss in the charge controller and about 1.5 volts drop in the wires. Such a module might well give as much as 24 volts on open circuit, but would not be able to charge a 24 volt battery.
A module intended for charging a 24 volt battery would normally have about 70 cells.

A 24 volt system should be slightly more efficient than 12 volts, but the choice of lighting and small appliances is much better at 12 volts. A 12 volt system is also safer, though 24 volts is fine with proper care.
I would advise against powering a modern boiler from a modified sine wave inverter, such appliances contain some sophisticated and expensive electronics.

[Lurkalot]

An update.
Always a good idea to have several quotes and we have had four companies in to look and the responses couldn't have been more opposite.
The first company , project solar came and looked and said " oh yes we can get 14 panels up there" and produced paperwork to show the returns. It all looked very promising. The second company said 14 panels was very optimistic and they reckoned 10 at most. The third company also said 10 may be possible but with it being a hipped roof it would mean 4 on one slope and up to 6 on another slope ( we have solar thermal already taking up space) . This , however , would require separate inverters or other additional hardware for each slope owing to partial shading of one slope in later afternoons. Again possible but the rep did say such extras all serve to raise the price and thus lower the viability of a system. The final company looked and were probably the most pessimistic of the lot saying that our roof was really not suitable and it would be really unlikely that we would ever recoup the costs of installation.

[biffvernon]

By the by, we've had our solar pv since 2010. They do say that panels degrade over time but a few days ago our 3.94kW system clocked a new one day record of just over 27kWhr.
Our supplier was http://www.ethicalsolar.org/ and I would happily recomend them.

[kenneal - lagger]

So now we should abandon all our solar installations because the subsidy method requires that someone pays for the subsidy?

[Little John]

So now we should abandon all our solar installations because the subsidy method requires that someone pays for the subsidy?

Of course you won't. But, make no mistake, your subsidized solar installations and the financial benefits those subsidies have conferred have been born on the backs of those who can least bear the burden.

[clv101]

So now we should abandon all our solar installations because the subsidy method requires that someone pays for the subsidy?

Of course you won't. But, make no mistake, your subsidized solar installations and the financial benefits those subsidies have conferred have been born on the backs of those who can least bear the burden.

Same as it ever was, of course. Nevertheless, I will bear witness to it every time I see or hear the kind of supercillious, self-satisfied, smug shite that the likes of Biff Vernon come out with on a daily basis

You are quite right here LJ, the FiT should never have been funded regressively from energy bills but rather progressively from general taxation.

However I suspect the latter option simply wasn't politically viable so we're left with the choice - fund from bills, where the poor take a disproportional burden and a small number of rich people get to make good (7%?) returns on their investment or not subsidise at all meaning we basically wouldn't have a solar industry.

The one good thing is that, thanks in part to these subsidies in many countries around the world the price of solar has fallen so much that soon no subsidy will be needed. At that point solar offers a major benefit, even to the poorest people in the world, offering decentralised power where they could never afford 'conventional' utility power.

The feed in tariff only came in in April 2010 - it'll be gone before 2020 with perviously installed systems maintaining grandfathered rights for a 20-25 year life from install.

When all's said and done, by 2030 some £8.6 billion will have been extracted from us, in proportion to how much electricity we buy and given to around 1 million (relatively wealthy) households. Is that redistribution of wealth worth it to deploy >10GW PV capacity in the UK?