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Harvesting Power When Freshwater Meets Salty
ckwu writes "As a way to generate renewable electricity, researchers have designed methods that harvest the energy released when fresh and saline water mix, such as when a river meets the sea. One such method is called pressure-retarded osmosis, where two streams of water, one saline and one fresh, meet in a cell divided by a semipermeable membrane. Osmosis drives the freshwater across the membrane to the saltier side, increasing the pressure in the saline solution. The system keeps this salty water pressurized and then releases the pressure to spin a turbine to generate electricity. Now a team at Yale University has created a prototype device that increases the power output of pressure-retarded osmosis by an order of magnitude. At a full-scale facility, the estimated cost of the electricity generated by such a system could be 20 to 30 cents per kWh, approaching the cost of other conventional renewable energy technologies."
Renewable is going nowhere until they're at parity.
No amount of greenwashing and tree hugging circlejerking will change the fundamental economics of this.
The problem here is you're not comparing apples to apples. The 'cost' of fossil fuels doesn't include environmental cleanup that isn't necessary with renewables. It also doesn't take into account the real cost - when you take out all the tax incentives for fossil fuels, the math becomes quite different.
Also, the cost of fossil fuels will continue to go up due to environmental laws and more difficult to process sources (like tar sands), fighting unnecessary wars to secure foreign oil sources; meanwhile, while the cost of renewable technology keeps going down.