Solar panels - more energy than they are worth?

[Martin]

my tip is to WAIT! - prices on pv panels should fall within the next couple of years
I'll be very interested in what they quote too!

[Imp]

I'll take the tip to wait then... can't run to four and a half grand right now - how can they justify nearly £7000 (inc grant) for such a system

I like the look of your wind turbines, I may read a bit more of your site then... *skips off*

[mattachinelee]

I just finished a conversation with my mum who tells me they had a quote for a solar panel system to heat their water (enough for just the two of them) and with the grant it would run to £7,000, which feels ineffective for them to recoup the cost when they are retiring at the end of the year.
Yet I had a conversation with a colleague today, who is preparing to travel with his family for a couple of years, who spoke about two £500 PV panels on the roof of his motor home giving all-year round charge to batteries which will give his family of four power for lighting, TV in the evening and to charge his laptop for his business use while he's on the move. His belt and braces approach is seeing him also considering a small wind turbine - the kind you get on canal boats, just in case the panels don't quite hit the mark on short cloudy winter days.
How can these two things both be true? I don't get it.

[Martin]

Hells teeth - what a rip-off price! - they should be paying somewhere about £2,500 for a system like that!!!!!
(stuff the grant, that usually doubles the price!)
As for the pv system for a caravan/motor home - £1000 has probably got him 250 watts of pvs, or thereabouts......that should on average give about 1kw/h per day - around a tenth of the average family consumption. SO, if you look at the fact he's not running any heavy current items like fridges, deep freezes and cookers off it, then that may well be enough (they probably use bottled gas for cooking/refrigeration)
However, sod's law being what it is, pvs work far less well in winter, often when you need the power most, so his idea of supplementation with a wind turbine is a good one! (but for one very large caveat - DON'T mount it ON the caravan/motor home - not if you want any sleep). It is easy to carry a sectional mast, and erect it closeby - if you can do that, no problems!

one we took to the Big Green Gathering


I hope that helps make sense of it - pv panels are pricey, but for caravan use are great, partcularly if you're careful about the size of appliances you're running

[Ranter]

My BF's Dad was asking about solar pv panels the other day. They have solar water-heating already & he's now interested in pv panels for other electricity needs. He's looked for, but can't find, a website/organisation/co. who can advise on needs & costs.

I said I'd read advise from someone in the know (Martin) that prices are predicted to fall in the next couple of years, but he's interested in doing something now.

Any suggestions of where he can get accurate information?

[Martin]

the facts are fairly simple - a KW of solar panels will cost around £3-4,000 - and on average, will give about 3kw/h of electricity per day, averaged over the year - so you'll be generating about £100-worth of electricity from those panels (which will be around 7 square metres)- and for the average home, you'd want three of those!......add to that the price of the grid-tie inverter and export meter, we're talking about being in profit in around 40 years!
The sums just don't work!
Compare that to a system we are putting together as a rather low-tech chp unit (complete with grid-tie)- initial cost, under £5,000, which will provide all the electricity you need if your unit is run for 3-4 hours daily (using 3-4 litres of any vegetable oil - included simply filtered wvo) AND will also make a significant contribution to the house hot water too!

[Stonehead]

Leaving aside the payback time (which is very long and usually longer than the lifecycle of many current panels), the life cycle assessment of PV is very complicated.

The technology is improving year on year, manufacturing processes are being developed, refined and simplified constantly and life cycles are extending.

You also have to look beyond the energy costs to the entire effect of PV development, manufacture, transportation and installation.

All PV technologies use non-renewable resources to varying degrees, with some resources in shorter supply than others. However, most of those resources are recoverable if a good end-of-life recycling programme is in place (which, by and large, it is not).

Also, many of the manufacturing process emit CO2 while some processes release other gases that either contribute to global warming or ozone depeletion.

In terms of life cycle emissions analysis, PV does fairly well but is still nowhere near as good as hydroelectric or wind power. In fact, on balance, PV is about on a par with biomass. Obviously, there are differences in their outputs of specific gases - CO2, SO2, NOx - and particulates, but by and large they're about the same overall.

Of course, life cycle emissions analysis is only part of the equation. Nuclear does very well out of LCEA as various interested parties like to point out, but its outputs are nowhere near as manageable, despite the nuclear industry's claims. (And yes, that was a pro-nuclear site but the emissions figures match those elsewhere.)

If you don't mind waiting for a hefty download and can get through the science, then Potential Health and Environmental Impacts Associated With the Manufacture and Use of Photovoltaic Cells is worth reading.

Personally, I think a lot of cowboys and "entrepreneurs" are jumping in to make a quick buck out of a fashionable and "eco-friendly" technology. You can be a good consumer and not feel guilty!

I still think the way forward is to use less energy in the first place, install the most efficient and eco-friendly solar hot water system you can afford (so no mains electric pump, no antifreeze etc) and only then consider what would give you - in your very specific circumstances - the most energy for the least impact and quickest payback.

[dibnah]

Exactly the embodied energy contained in a PV pannel considering most are made in japan can't at the moment justify to me replacing my system which I use effectively. A solar hot water system would be a great saving enviromentally for our house but we can't afford it sadly and I would also like to supplement it in winter with wood fired boiler but we live in a smoke free zone and have a gas fire with a back boiler again cost, embodied energy if starting a new build then it would be an option but at the moment I'll stick with turning lights off when not in use. We need to learn to live simpler to use less and more importantly realise that its not a big deal.

right I'll just get off this high horse because it's starting to gallop

[caithnesscrofter]

I'm with stonehead.. the only answer is LESS energy. My brother-in-law has ZERO energy. And has lived like that for more than 10 years at least. No lights, no nothing. And goes everywhere by horse and cart or just on horseback or hitchhikes. This works for him. Although I do believe he's been cheating as someone offered him a gas light for his tipi! LOL Knowing Mark he probably doesn't use it.

In the city..tho.. alot of people do not have much of a choice. I'm still living part-time in Edinburgh in a rented flat. I've got a washing machine.. which I use... in the yurt I do not.. I handcrank my laundry everynite before bed. In the city.. I've got a gas cooker.. I use it. In the yurt, I've got a four dog stove that has a baffle making it super efficient to cook on... plus has a 3 gallon hot water tank on it that heats as I cook. I also use this same stove for heat which I burn wood, peat and horse poo in... but, will soon be putting a rocket stove in there which is even more efficient when I build the earthern floor for the yurt. In the city.. I've got gas heating and gas hot water. Here I flush.. there I poo in a bucket and compost it. For lights, in the city... I use lecy except in two rooms when I bring home my portable Glowstars which have 4 small amorphus solar panels apiece. I use these as the only light source in the yurt. I've also another 40watt solar system that gives power for my laptop battery recharge. These work really well.. and in my situation being off grid up north... it is really the cheapest and best system I can afford. As of February I will be in Caithness full time and have cut my electrical goods down to this. My laptop, my two lights and a recharger for my digi camera. And very rarely plug in my printer. That's it! If I get a borehole drilled I will probably need a small wind turbine for the pump. In the event of power tools being recharged.. I've got a two battery system in the defender that is permanently charged off the car battery and the inverter from the 40w panel system can be wired up to take other mains items for recharging. What the hell more does a person need? My laptop is my tv for emergenciy news and the odd Scotland game LOL, my phone and my connection to the world and a massive resource of information and (misinformation at times:-). LOL

I don't believe in putting more pressure on the grid... it is already to over worked and it drives me nuts that the highlands are covered in pylons.. as I'm too aware of the dangers of electromagnetic polluction. Solar systems give off emf's but, with a EM meter you can rent you are able to position them so they are a safe distance.. which rules out the roof most of the time. Depends on the size of the array. But, no matter where you live if you are converting your power source to be less dependent on the grid system you are doing well.. i believe it helps to have various sources too.. not just one system... in case stuff goes haywire you've got some back up.

Convenience items ought to be taxed big time and with that money spent on renewable energy household grants. I'd like to see electric tin openers cost £5,000 and microwave ovens that cost £10,000. LOL