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libspero

Why Are Solar Panels So Expensive?

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Ok, I appreciate that we are still some way from having decent low cost (thin film) solar technology, but in the mean time thought I would look at the cost of building a panel against the cost of purchasing a pre-fabricated one.

Typically, solar panels are made up of individual mono-crystalline wafers, connected up and placed in a weather resistant frame.

benefits.jpg

Case 1 -Pre Fabricated

A typical 150W panel from Maplin costs £800. Linky So if you wanted to make, say a 1.5kW array, you would need to spend £8000.

Case 2 - Home Made

I then wondered how much it would cost to make yourself. An individual mono crystalline wafer producing 1.9W costs 87.5 pence. Making our 1.5kW array cost £690.

How do solar module manufacturers justify charging £7,310 for a frame? :blink:

Anyone understand the disparity or is it really just pure greed margin?

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Ok, I appreciate that we are still some way from having decent low cost (thin film) solar technology, but in the mean time thought I would look at the cost of building a panel against the cost of purchasing a pre-fabricated one.

Typically, solar panels are made up of individual mono-crystalline wafers, connected up and placed in a weather resistant frame.

benefits.jpg

Case 1 -Pre Fabricated

A typical 150W panel from Maplin costs £800. Linky So if you wanted to make, say a 1.5kW array, you would need to spend £8000.

Case 2 - Home Made

I then wondered how much it would cost to make yourself. An individual mono crystalline wafer producing 1.9W costs 87.5 pence. Making our 1.5kW array cost £690.

How do solar module manufacturers justify charging £7,310 for a frame? :blink:

Anyone understand the disparity or is it really just pure greed margin?

Where do you get the quote for the second case, out of interest?

Maplin are never the cheapest even for minor PC bits and pieces so I imagine a lot of that £800 is the retail 'margin'. If you were to go to a domestic solar PV company I think the rate is more like £3000-£5000 per kWh (I keep hearing ~£15,000 for a 4kWh array). That is fully fitted, so it includes the inverter (at least £1000), wiring, labour, the housing for the panels (I'm guessing your figure is for the naked silicon wafers - they're fragile and need protecting in glass etc.).

Or do you think everything should be sold at cost?

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Where do you get the quote for the second case, out of interest?

-SNIP-

Or do you think everything should be sold at cost?

Apologies.. 1.9W cells

And no, I understand that everyone has to make a crust. This is not so much a dig at solar installers as the module manufacturers. I would expect a retailer to add a 50% margin on an item this size. So say a panel cost of £4000. Even if the manufacturer wanted a 50% margin as well, that is £2000 cost. As far as I can tell the component cost to a panel manufacturer can't be much more than £500-£1000 for the items involved (and the bulk discounts I would expect they would get).

I understand there are a lot of assumptions there. I guess I am also suspicious that naked cells are so hard to come across.

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Apologies.. 1.9W cells

And no, I understand that everyone has to make a crust. This is not so much a dig at solar installers as the module manufacturers. I would expect a retailer to add a 50% margin on an item this size. So say a panel cost of £4000. Even if the manufacturer wanted a 50% margin as well, that is £2000 cost. As far as I can tell the component cost to a panel manufacturer can't be much more than £500-£1000 for the items involved (and the bulk discounts I would expect they would get).

I understand there are a lot of assumptions there. I guess I am also suspicious that naked cells are so hard to come across.

same shop is selling damaged cells for the same price... bizarre

http://shop.knowyour...ocrystalline_pv

how are you calculating 150w from your link?

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I noted the slightly chipped disclaimer.. although I interpreted 16.5% efficiency to mean the cells are 16.5% efficient as opposed to 24.5% efficient as you might more usually expect from mono crystalline cells. I guess it would be worth buying a couple units first though just to check this..

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how are you calculating 150w from your link?

1.5kW / 1.9 = 790 units

£63 / 72 = £0.875 per unit

1.5kW = £691.25

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Try Navitron for panels. You can get a UK manufactured polycrystaline 205W panel for a bout £450. Im sure with a bulk order you could haggle that down a bit

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Try Navitron for panels. You can get a UK manufactured polycrystaline 205W panel for a bout £450. Im sure with a bulk order you could haggle that down a bit

Thanks Kurt.. £3,300 for a 1.5kW system is getting warmer...

I should add that I'm not actually in a position to buy anything (don't think the landlord would be impressed.. plus flat), I just like to take an interest in things from time to time. For a future project I'd be quite keen, though if I was going to do it I would be tempted to go off-grid and re-wire the house for 12VDC with only limited inverters for powering 240V units.

Just think how much that would knock off the value of my future house :lol:

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I noted the slightly chipped disclaimer.. although I interpreted 16.5% efficiency to mean the cells are 16.5% efficient as opposed to 24.5% efficient as you might more usually expect from mono crystalline cells. I guess it would be worth buying a couple units first though just to check this..

This is probably why, together with the chipped edges. The yield for the high efficiency cells is likely to be significantly lower than the yield of crappier ones, and chipped edges will basically prevent their sale to a PV panel maker (simply to expensive to test every panel, match up efficiencies etc). The cells on that page are actually selling for significantly less than I pay in my lab for the bare unprocessed silicon wafers that would be required to make them. Whilst a manufacturer would get bulk deals on silicon that are far cheaper than my hundred or so wafers a year, those prices looks like they're probably not far off cost price, if not below. It's not dissimilar to the reason that intel sell multiple clock speeds - they plan to make everything at the high speed but some don't work as well as others, so they sell them as a lower clock speed unit.

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This is probably why, together with the chipped edges. The yield for the high efficiency cells is likely to be significantly lower than the yield of crappier ones, and chipped edges will basically prevent their sale to a PV panel maker (simply to expensive to test every panel, match up efficiencies etc). The cells on that page are actually selling for significantly less than I pay in my lab for the bare unprocessed silicon wafers that would be required to make them. Whilst a manufacturer would get bulk deals on silicon that are far cheaper than my hundred or so wafers a year, those prices looks like they're probably not far off cost price, if not below. It's not dissimilar to the reason that intel sell multiple clock speeds - they plan to make everything at the high speed but some don't work as well as others, so they sell them as a lower clock speed unit.

Interesting. May I ask roughly the cost of a single 6" wafer these days? (new).

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Yes, thing is I don't think people realise that current PV panels are big silicon wafers. They are similar to the silicon wafers used to make computer processors, etc. Obviously not as demanding, but still delicate and prone to faults. Not to mention the base cost of extracting silicon from its ore (basically sand). Hence the cost.

There is a lot of research going into making PV panels out of other materials, e.g. plastics, so that they will be cheaper to make but no commercially useful things yet, afaik.

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Interesting. May I ask roughly the cost of a single 6" wafer these days? (new).

Varies widely depending on the quality you want, doping level (common doping levels are cheaper) etc. In my case, looking at relatively 'low' semiconductor quality reclaimed 100 mm ($") wafers, but unusually high doping, I pay about 10 pounds a wafer with a MoQ of 25. I don't get 6" very often but a standard quality and doping 6" could be about £20 I seem to remember.

Solar cells are much lower grade silicon and usually polysilicon these days too I think, which is cheaper, but a 6" wafer would still be about a couple of pounds.

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Varies widely depending on the quality you want, doping level (common doping levels are cheaper) etc. In my case, looking at relatively 'low' semiconductor quality reclaimed 100 mm ($") wafers, but unusually high doping, I pay about 10 pounds a wafer with a MoQ of 25. I don't get 6" very often but a standard quality and doping 6" could be about £20 I seem to remember.

Solar cells are much lower grade silicon and usually polysilicon these days too I think, which is cheaper, but a 6" wafer would still be about a couple of pounds.

Thank you.. sounds like those cheap ones really are cast-offs (or incredibly good value depending on your POV :D)

I guess your reclaimed wafers come from Purewafer? I think they have their own line of PV products too.

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Thank you.. sounds like those cheap ones really are cast-offs (or incredibly good value depending on your POV :D)

They are probably both - can't be used for commerically manufactured panel, but good bang for buck if making your own panels from scratch.

One reason panels cost so much in the UK is the schemes set up to promote olar power, without those market would be a lot more competitive!

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Yes, thing is I don't think people realise that current PV panels are big silicon wafers. They are similar to the silicon wafers used to make computer processors, etc. Obviously not as demanding, but still delicate and prone to faults. Not to mention the base cost of extracting silicon from its ore (basically sand). Hence the cost.

Indeed.. A lot of the cost comes from the power consumption required to melt the silicon.

I heard that it's standard practice to build a dedicated coal-burner next to each ingot/wafer factory ;)

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A typical 150W panel from Maplin costs £800.

I quick look at ebay.co.uk shows 185W panels at £274. Thus the fault is in quoting an expensive outlet.

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I quick look at ebay.co.uk shows 185W panels at £274. Thus the fault is in quoting an expensive outlet.

I'm not sure about buying second hand panels off some cowboy on eBay.. But I take your point that Maplin are not the cheapest.

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I'm not sure about buying second hand panels off some cowboy on eBay.. But I take your point that Maplin are not the cheapest.

It's no problem. I bought 4 x 175W panels brand-new from an Ebayer - an installer who had a number of units left over. Those guys buy them in the pallet-load. I have also bought ex-demo units (200W panels). Both times I paid about £3 per Watt, but now, as Kurt points out, prices have dropped somewhat, to about £2 / Watt. Solar cells are just very, very large diodes, about the simplest and most reliable piece of electronics. They don't age significantly, about 1% drop in output per year. Small panels are proportionally more expensive than large ones, i.e. 10 off 20W panels will cost you more than one 200W panel..

You will also need either a battery controller, or a grid tie inverter to be able to use the things sensibly.

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Try Navitron for panels. You can get a UK manufactured polycrystaline 205W panel for a bout £450. Im sure with a bulk order you could haggle that down a bit

Who can wire a system into the mains and will they wire in a self-installed navitron system?

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I'm not sure about buying second hand panels off some cowboy on eBay.. But I take your point that Maplin are not the cheapest.

A ) Solar panels are not simply the silicon cells. The cells are stuck to aa aluminium backing and encapsulated in plastic after being wired up. They are then give a guarantee up to 25 years. People who wire their own cells report failure in 7-10 years. It makes a major difference to the economics.

B ) Your prices are way, way off. The lowest price is by the pallet. <£1 per watt (plus shipping etc)

http://www.affordable-solar.com/store/solar-panels-by-the-pallet

These are particularly attractive to me as they are designed for Canadian levels of snow. $1.59 per watt.

http://www.affordable-solar.com/store/solar-panels-by-the-pallet/csi-cs6p-230P-watt-solar-panel-pallet

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I don't know if solar panels attract VAT in the UK or not, but you can always import panels from the US or china.

The offers I am getting for crystalline panels around this time is 0.84 euro cents / Watt. (about 90p per watt). These are panels with 5 year manufacturing / 20 years 80% power generation warranty. Admittedly this is not retail price.

Retail price from a reputable dealer in the US is more expensive http://www.sunelec.com/ but its still about 95p per Watt, so your 1.5kW panels would set you back about 1300 pounds for panels (add inverter, mounting etc... and it would be about 1700 UKP total).

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Sun elec is selling panels for $0.74/W with a minimum order of 10 units (about what you need).

the panels work out to $1110 total (about 700 pounds for 1.5kW).

Seems to be the best price around.

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  • 309 Brexit, House prices and Summer 2020

    1. 1. Including the effects Brexit, where do you think average UK house prices will be relative to now in June 2020?


      • down 5% +
      • down 2.5%
      • Even
      • up 2.5%
      • up 5%



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