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Ty Gwyn

Wind v Solar

Thought this might interest a few of you with knowledge of generating ones own electricity,

Recently we have been doing some testing as our roofing division supplies and installs solar panels, our market isn't the domestic market but the industrial market where the companies know the real facts which are that they will pay out more to have the solar panels then they will make in savings and are prepared to offset this loss against tax and by claiming the subsidies, they want them more as a part of their corporate environmental policy.

I do a lot of off roading and have built my own expedition vehicle using all my engineering experience and it was built to a high specification to meet our requirements rather than down to a price and it was all home built with its super insulated Kevlar double skinned body, enough water, fuel, gas, and food capacity for 4 weeks totally off grid and more importantly its two massive battery banks with a capacity of 3750 amps each and they were free, yes free courtesy of our nuclear submarines and still under warranty.

One day when I was in the office all day I went to work in it to give it a run and circulate the fluids and one of our directors saw it and asked how I powered it and I showed him the twin 320 amp engine alternators and he said no, I thought you didn't run the engine when you stopped, so I showed him the two portable wind turbines I use; one is a 12 volt X 1500 watt portable unit which fits to the back of the vehicle and is assembled and erected in around 2 minutes and fixes into dedicated clamps while the second unit has clamps at the front of the vehicle and a base and guy ropes so it can be attached to the vehicle or used as a free standing unit and when he saw the output they provided compared to a solar panel he became interested in them.

During July and August (not finished yet) we have been doing some testing and this is like for like to compare solar panels and wind turbines in a side by side test; the reason being that due to the downturn in the economy we are fitting fewer solar panels as companies know they will never recoup their costs (initial investment) and aren't having them installed and he is looking for an alternative but he originally dismissed my idea of small wind turbines as they were not in the peoples minds due to the heavy promotion of the solar industry and its inefficient solar panels.

To conduct fair and accurate tests we installed a solar system of a specified wattage on the test rig in the middle of a field and an equal sized wind turbine about 5 metres apart so they were run under the exact same conditions, and we managed to get some of the latest development solar panels which are currently state of the art and are so new that they won't even be on sale for about 12-18 months and will be very expensive. Testing was done over a full 24 hour period on three separate occasions for each test to give an accurate reflection of performance under normal UK conditions, albeit summer conditions. While we have tested numerous outputs of both solar and wind systems the results were remarkably similar across them all so instead of putting up lots of technical data I will give the results of the 300 watt systems. WE decided that in terms of efficiency we would use them at 12 volts as this is the most efficient use of both systems as opposed to mains voltages.

300 W at 12 volts = a maximum output amperage of 25 amps and over the three 24 hour periods of testing the solar panel tested averaged 1.21 amps per hour and even during optimum conditions it couldn't hit 15 amps output for above 1 minute and only hit above 10 amps for about 20 minutes.

Meanwhile, the wind turbine despite being a portable, compact item averaged 11.74 amps per hour over the same three 24 hour periods and regularly ran above 20 amps for sustained periods of over 15 minutes and hit its peak 25 amp output on several occasions which makes it viable for charging 12 volt batteries or charging other sizes of battery packs such as 24 or 48 volt systems as it delivers plenty of power to charge sufficiently large battery packs for inverter use.

Now we can look at costs, the solar panel is not currently on sale and will cost 1000's when it goes on sale and in our testing it provided 29.04 amps total average output; compare this with the portable wind turbine which was a 14" (350mm) diameter unit and cost a massive 140 including charge controller which delivered an impressive average of 281.76 amps over the same 24 hour testing periods.

From a cost perspective it stacks up as we used an average wind turbine unit anyone can buy and set up themselves, at 14" diameter (this is the blades) it isn't obtrusive, it can be mounted on a shed, barn, or garage roof as a permanent fixture, it makes no noise in operation unlike the large units dotted (blighting) the countryside, and it can be run with a variety of battery pack voltages. It provides sufficiently high outputs to charge massive battery packs and in industrial use it can power anything which can run off 12 or industry standard 24 volt systems which are generally used around European factories, you can incorporate 12 volt LED lighting or even run most laptop or base station computers directly from 12 volt.
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Mistress Rose

Interesting Ty Gwyn. I didn't know you were into other forms of energy production too.

A question about your small wind turbines. How do they cope with the sort of turbulent air you would get round houses and trees? This is a problem with some that are sold for domestic and small scale industrial use I know.

I don't think thsts Ty Gwyn experience, rather a copy from the link posted at the bottom.

Solar PV should cost 1000's, it's a relatively inexpensive way of obtaining power. Small turbines on shed or house roofs are terribly inefficient but if done properly, and if you can get planning permission, are cost effective.

You shouldn't view this as wind vs solar. They are complimentary.

The units do not give me confidence in the article.

It's anecdotal at best.
Ty Gwyn

Right Pilsbury,its a post by an ex Mining engineer who works for a solar company,
He has gone off grid with all kind`s of alternative energy projects,sounds a clever guy indeed,
Reason i posted the article was to see if his reasoning add`s up,when scrutinized by the electrical knowledged here.

Why would you want to compare solar and wind directly in such a test? It only makes sense for a specific instance and location and even then you'd probably want a mix for best effect.

I'm not sure he's understood the philosophy of renewable energy.

Something that should be taken into account in this argument is the longevity & maintenance issues. The solar PV panels at the CAT institute that have been in place for over 25 years are still running at over 80% of their original efficiency according to a friend who studies these things.
I very much doubt any wind turbine would be able to do the same without regular & expensive servicing & replacement parts.
Attaching small turbines to buildings in unsuitable wind conditions where there are a lot of eddies can cause structural problems.
Consequently house insurance firms don't like them.
& efficiency is debatable.
Wind generating is best done on a larger scale, it does become more efficient the bigger it gets, Solar PV is efficient on any scale from on vehicle battery charging to the roof of the huge Tesla factory in the Californian desert.
All in my humble opinion.

Commercially we've not progressed solar, mainly due to changes in the the tax regime. We built this instead:


You shouldn't view this as wind vs solar. They are complimentary.

Ty Gwyn

Look`s like i was wrong in thinking some here might find it interesting,

Not that anyone has debated his figure`s or calculations.

Not that anyone has debated his figure`s or calculations.

They're not particularly meaningful in the context he's provided them.

He talks in general terms e.g. "get some of the latest development solar panels which are currently state of the art and are so new that they won't even be on sale for about 12-18 months and will be very expensive" which means nothing.

He says nothing about load profiles and usage, charging efficiencies, storage utilisations, cost effectiveness, required inputs etc. His units of energy are incorrect, he should be quoting Watt.hours not amperage, and he make no references to suppliers, makes, models or anything particularly meaningful.
Ty Gwyn

Considering he has converted his house/smallholding to be completely off grid,doing the work himself,
Considering he work`s for the solar company that has dealing`s with the supplier of these new panel`s,he`s hardly going to post the details before they come on the market,
I guess the guy know`s something about what he does,

Considering he posted this on a Mining forum,frequented by electricians,he must also be brave or daft,lol.

If you disagree with his calculations,you could always log into that forum and debate the issue`s with him.

The mistakes, inconsistency & bias are so huge I CBA to even start to debate it with someone that has already made their mind up. Ty Gwyn

Do point out these mistakes,inconsistencies and bias`s,

I`ll point them out to him,as i don`t often agree with him,lol
Mistress Rose

One thing to consider with wind v solar is that wind power can probably be considered a mature technology. Although we have only been generating electricity with it for a relatively short time, we have been using windmills of various sorts for centuries. In the form it is being used to produce electricity, solar power is very new; I had a very early solar cell in the late 1960s produced by Bell Laboratories, and at that time something of a novelty.

A lot of work is being carried out on solar cells, and I think over the next 10-20 years we will see great improvements in them. There are several solar farms round here, and one advantage they have is that they are generally less intrusive at ground level than wind power. Aesthetics I know, but important if people are to accept them. On the down side they take up a lot more room than a windmill.

Interesting subject Ty Gwyn, but don't know enough about it to debate on anything other than acceptance by the public level, and to some extent suitability of sites.

the elephant in this equation is water,from cragside via the hoover dam to modern flow turbines moving water has proved that it has the reliability and sufficient harvestable energy to make development of a variety of systems a practical solution to the problem.

over a century and a half various rigs have been developed that can harvest useful energy from almost any example of moving water,perhaps it is under developed because it works .solar and wind seem to rely on tax breaks ,getting 15% of all offshore wind the royalties back to the royals which makes their promotion of and investments in offshore wind a rather good deal,government greenwashing etc etc .

it might not be sunny ,it will be night or it might be the wrong sort of wind but the tide will ebb and flow in a very predictable way and apart from 4 slack spots a day is a continuous energy source

ps the ones in strangford loch dont seem to mince all the fish either

Not been mentioned so far

When we have a high pressure system in place, sometimes over the whole country, then it is sunny, with low, or no winds. This can happen in the middle of winter - lovely crisp sunny days - and in the UK the sun is a lot lower in winter than in summer. At that point solar PV is not performing nearly as well as it would in summer and the wind turbines are not turning at all. So standing a turbine and a solar panel in the same location - interesting but it depends when you chose to do it and the weather system at the time.

Go and look at the Renewable Energy Foundation website and their various studies. They base their work on real time outputs from working commercial solar and wind power.

They have data on most renewables - including slurry and other bio ones.

Another interesting one to google is Eigg Electric - the island of Eigg has its own power generation and distribution network with solar, wind and hydropower. Also discusses the limitations on the usages (which seem pretty reasonable to me).

My personal view is that

1. We need to work to reduce world population (see folks like Population Matters)
2. We need to work to reduce individual consumption (whatever the source of the electricity).

It will have a much bigger effect than moving more and more generation to renewable sources plus it makes powering the country by a proportion of renewable more feasible as we just don't need as much.
Mistress Rose

Dpack, you are right about the tidal power, or other hydro schemes. There are still some parts of the country that can't use either though; where there are few rivers, no sea, and no suitable sites for dams, are not going to generate much for instance.

One reason that fossil fuels have been used for some time to generate electricity is that they can be regulated as needed. So far, apart from hydro, which is sometimes used in conjunction with back pumping schemes, none of the renewable sources are capable of regulation on an as needed basis rather than an as generated basis. Hopefully power storage systems of various kinds will eventually be capable of allowing this to happen.

This seems an appropriate place to link to this

Why renewable energy won't work.

What do you all think?

renewables will never permit the human race to cut CO2 emissions to the levels demanded by climate activists.

How are we defining "activists"?
In my book, they tend to be the extremists, so are perhaps calling for unreasonable cuts?

the most active activists are the folk who make billions a day from extracting,processing and trading fossil fuels to burn.

i spose the immans that have recently suggested fossil fuel is at odds with "stewardship"are activists as are the various govs that signed up to kyoto(although they have mostly failed to comply or have gone for nukes which are another hot kettle of slightly dubious fish)

anyway back to the thread i recon both wind and solar have a small place in the big picture and can be a good option for micro scale schemes although massive desert based solar arrays could be a sensible move but until large scale energy storage is sorted owt that only works part time is never going to be more than a detail

for expedition power a portable solar/wind combo with some good batteries is probably a clever rig.

The "seven day" zealots will agree with the "con sensus" Laughing Laughing
Mistress Rose

We need to look at a range of ways of producing the power we need. Some of them may turn out to be dead ends, but others may be worth pursuing. Water power, in spite of my previous post, is definitely one of those. It won't produce enough power for all our needs, but it will add a steady production as a base line.

Many years ago, when solar power production was in it's infancy, it was calculated that there was enough sunlight falling on Egypt to give more than enough power for the whole world. Again, even if we could put vast solar arrays in desert areas, it wouldn't be the sole answer, but arrays in suitable places will provide some power. If the array produces more power over its lifetime than is used in its production, it is a positive input, especially if the materials can be recycled.

At this time all we can do is chip away at the use of fossil fuel as actively as we can. It should have started a long time ago; we were interested in this when we were first married over 40 years ago, and not enough has been going on fast enough in the meantime to give us the full ability to stop using fossil fuels for energy.

We need to look at a range of ways of producing the power we need...
Producing, storing and using.
Mistress Rose

True Hairyloon.
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