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Cheap Solar Panels Made With An Ion Cannon
MrSeb writes "Twin Creeks, a solar power startup that emerged from hiding today, has developed a way of creating photovoltaic cells that are half the price of today's cheapest cells, and thus within reach of challenging the fossil fuel hegemony. As it stands, almost every solar panel is made by slicing a 200-micrometer-thick (0.2mm) wafer from a block of crystalline silicon. You then add some electrodes, cover it in protective glass, and leave it in a sunny area to generate electricity through the photovoltaic effect. There are two problems with this approach: Much in the same way that sawdust is produced when you slice wood, almost half of the silicon block is wasted when it's cut into 200-micrometer slices; and second, the panels would still function just as well if they were thinner than 200 micrometers, but silicon is brittle and prone to cracking if it's too thin. Using a hydrogen ion particle accelerator, Twin Creeks has managed to create very thin (20-micrometer), flexible photovoltaic cells that can be produced for just 40 cents per watt; around half the cost of conventional solar cells, and a price point that encroaches on standard, mostly-hydrocarbon-derived grid power."
The energy stored in a flywheel is I * omega ^ 2. With the materials we have available now and the size you want to allocate to such a thing, manufacturers have found it works best to have a flywheel with a modest moment of inertia and crank the rotational rate way up high (100,000 rpm for starters). To keep the flywheel from spontaneously shattering, high speed flywheels are mostly made from carbon fiber. And with the flywheel spinning so fast, the only way to keep them from losing energy to friction is to have them spin in a vacuum on magnetic bearings. Then you add in a high efficiency motor/generator, with some serious power electronics to commute the phases at ~kW power levels. These are all proven technologies (see Beacon Power), but compared to a bank of lead acid batteries, it isn't an affordable solution for a home.
Sure, solar power doesn't produce infinite power per area. But that doesn't matter. In fact, I'd argue it still produces quite a lot.
It's been known for a long time that the price of manufacturing per watt is the important thing for solar, and that goes down all the time. There is no known lower limit to prices here.
I think you're underestimating how much space there is when you say solar isn't very dense. A good sunny day will give 1000W solar input for one square metre. There are a million square metres in a square kilometre, meaning a gigawatt of solar input. That's a typical nuclear reactor's worth. But not all of that can be used. Let's assume 10% efficiency, meaning 10 square kilometres/nuclear reactor. Add half for support equipment and it's 15 square kilometres.
That's a square less than four kilometres wide. For a nuclear reactor this would be an acceptable safety zone - it's pretty small really.
There is plenty of space for solar if it only becomes cheap enough. It is already cheap enough in places like Hawaii, and it will only get cheaper while fossil fuel prices will keep going up.
You will only get 8 hours of usable sunlight per year if you have a solar tracker and live in a particularly sunny spot. Here in Sydney, (which is on the same latitude sun wise as LA for you North Americans) PV installers base calculations on on 4 hours at the rated value for fixed PV.
So a 200w panel costing $600 would give you 300 KW per year. At our electricity prices that is $68 a year, so paid off in 9 years and a ROI of 280% over the 25 years of installation. Sounds okay. Sounds even better when you take into account that buying grid energy from renewables in Australia commands a 40% premium on the price, and that there is a connection fee of $160 per year, and that energy prices will continue to rise.
The problem is that the cost of the panel is only about a third of the cost of the installation for home solar, even if you do it yourself. To make matters worse the batteries have a much shorter life than the panels.