Slashdot Mirror
Researchers Generate Electricity Using Seawater and Sunlight
Slashdot reader sosume writes: Scientists at Osaka University have created a new method to use sunlight to turn seawater into hydrogen peroxide which can then be used in fuel cells to generate electricity. It's the first photocatalytic method of H2O2 production that achieves a high enough efficiency so that the H2O2 can be used in a fuel cell.
It's easier and safer to transport liquid H2O2, according to the article, and while its total efficiency is much lower than conventional solar cells, the researchers hope to get better results by using better materials.
It's easier and safer to transport liquid H2O2, according to the article, and while its total efficiency is much lower than conventional solar cells, the researchers hope to get better results by using better materials.
The point of this technology is not the production of the energy, but it's ability to use to store that energy for future use, like when it's night.
mdsolar is a shill who ignores the huge problems of cost and load balancing related to PV generation.
Energy efficiency and economic efficiency are totally different. Economic efficiency is "how much effort and resources do I have to expend to get this thing to work?" You can have 100% energy efficiency, but if its economic efficiency is $100 per kWh, nobody is going to use it. It is literally cheaper to build a larger system with lower energy efficiency to harvest the same amount of energy. This seawater method could have 0.1% energy efficiency, but if it economic efficiency is $0.05 per kWh it would be a tremendous breakthrough.
mdsolar doesn't care about economic efficiency, which is why his "solutions" are pointless for the real world. The reason PV solar languishes at below 1% of electrical production is not some grand conspiracy. It's because PV's wholesale production cost (after factoring in construction, financing, maintenance, lifespan) is up around $200-$300 per MWh. Coal is around $40 per MWh, around $350 per MWh if you include the environmental and health damage it causes that the IMF estimated in it's "$5.3 trillion subsidy" report. Gas around $60. Nuclear is around $60 ($90-$100 for new construction). Hydro around $30. Wind around $70-$100.
PV has dropped to about $125-$150 per MWh in the last few years, but it remains to be seen if that's real gains or due to dumping by Chinese manufacturers to try to drive other manufacturers out of business. Even if real, it still remains the most expensive source of electricity, which is why it's stuck at below 1% of production.
H2O2 is not a particularly good way to store energy. It is a strong oxidizer, and can burn human flesh unless diluted down to about 3%. It will ignite many substances on contact. It is also thermodynamically unstable, and can explosively decompose if it gets too hot, or comes in contact with something flammable. When it decomposes, it produces concentrated oxygen, which can cause fires to burn out of control. It is nasty stuff.
We're talking about hydrogen peroxide, right? Like people use to put on cuts to keep them from getting infected?
And rocket propellent: https://en.wikipedia.org/wiki/... .
The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.