Scientists at Sheffield University have figured out a new way to separate particles of algae from the water that it grows in through the use of micro-bubbles. This isn’t a brand new idea – micro-bubbles have been used to purify water and separate out algae for a while now – what they’ve figured out is a method of doing it cheaply and with much lower energy requirements than previous techniques. This should reduce the costs for harvesting algae for producing food or biofuels – whether it’ll be enough of a reduction to make a difference is another question, but every little bit helps.
Category Archives: Energy/Mining/Resources
Typically, the silicon wafers in solar cells are cut from blocks of refined crystalline silicon with a saw, producing silicon sawdust and thus wasting about half the total block. A solar startup is working on a way to peel off thin sheets of silicon, without as much cutting and waste. Since refined crystalline silicon is one of the larger costs in solar cell manufacture, this could be another avenue to reduce the price of solar energy.
Ars Technica has an interesting summary of an article in Nature on peak oil, touching on the economic impacts that the stagnating supply of oil will have. I’d like to say more about it, but the numbers have varied so much since I became aware of the “debate” over peak oil that I’m just going to tell you to click the link if you want to read more.
“Liquid air” means air – the stuff you’re breathing right now – chilled and stored in a liquid form at -256 degrees Farenheit. When it’s injected into the engine along with a room-temperature heat-exchange fluid (which won’t freeze in the engine), the liquid air boils – it turns into a gas, creating a lot of pressure and powering the engine.
The “pros” of this idea (compared to hydrogen, at least, which is the other volatile gaseous fuel being considered as an alternative to hydrocarbons) are that A) industry already produces liquid gases in huge quantities, B) there’s already well-established distribution infrastructure for it, C) it’s easier to store than hydrogen, and D) there’s much less of a chance for it to explode.
There are still big hurdles for the tech, if it wants serious consideration. First, we need to know how much energy it takes to liquify air, transport it, and then use it in a car engine – the stuff is a way to store energy in liquid form, so the efficiency of the process is important. Storage is also a problem – liquid air evaporates even under pressure and while insulated, so if you leave your car alone with a full tank of “gas,” and come back after a month, you might find it’s emptied. That might be a bit of a problem. And let’s not forget that it’s still a gas (in liquid form, admittedly) being held under pressure – it will go “pop” under the right (wrong?) conditions, and is quite capable of creating a burst of shrapnel.
TL;DR – cool idea, don’t know if it’ll work.
Ocean-based wave energy is tricky to harvest. The energy is there, and is fairly constant, but the hardware necessary to harvest large quantities of it has so far proven to be unequal to the task in economic terms. This is partly due to the fact that the energy is diffuse – there’s a lot out there, but it’s spread out over a large area of ocean surface. But the problems the industry’s faced have also got a lot to do with how badly electricity and sea water mix: wave-power generators need to be well sealed and insulated in order to function in the ocean, which really ups the capital cost.
Now, what if you moved where the power was generated, so that you didn’t have to worry about seawater leaking in and frying your generator? That’s what a company’s trying to do in England, by using wave energy to pump water into a reservoir on land, which can then function as a gravity-powered hydroelectric plant. Think of it as a miniature Hoover dam near the shore: pumps in the ocean use wave energy to pump water up into it, and as the water flows back down to the ocean it generates power.
The big question is, how much will it end up costing per MW? They’ve got some promising estimates, but we’ll have to wait and see if it actually lives up to their promises.
Surprise! The Chinese have a hinky economic system.
The reason for the sarcasm is that a US government investigation into the Chinese solar panel industry has found evidence that Chinese manufacturers are selling solar panels for less than the cost to make them, which really hurts their competitors (and them, but they’re getting free money from the Chinese government, so they’re doing well at the moment). This shouldn’t be much of a surprise to anyone.
For over a decade now, the Chinese government has been making money easily accessible to Chinese manufacturers in the form of low-interest loans. This has provided many jobs and sparked the Chinese economy into a huge boom, but it’s also allowed the companies to become bloated and inefficient (after all, why bother with efficiency when you can just take out another loan?). The loans have become essentially free since the Great Recession started, which has made the bloat grow even faster. This is, if you’re curious, the same situation that Japan was in in the late 80s, just before it fell into its current multi-decade stagnation.
So, yeah. Not at all surprised that the same thing’s been going on in the solar industry over there. The only question is what the US (and others) are going to do about it. This situation leaves China’s competitors with three bad choices: either take advantage of the artificially cheap goods for sale (driving their own solar industries out of business), subsidize their solar industries (which would cost a lot of money), or slap import tariffs on Chinese solar panels, which would very likely start a trade war. There aren’t really any good responses to this, the way I see it.