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I've been a huge proponent of "green" energy for years, and after watching it for those years, it's becoming more and more obvious the technology just isn't the
by Caerus 15y ago
I've been a huge proponent of "green" energy for years, and after watching it for those years, it's becoming more and more obvious the technology just isn't there yet. The best we can do is pump more money into research and ignore these poorly planned start ups that are only profitable due to subsidies. Every major type of renewable energy has some aspect which makes it at least a decade and several breakthroughs away from viability.
Cellulosic/Algae Ethanol: About an order of magnitude off on cost, many orders away on capacity. They are still immature technologies but seem to have a lot of promise.
Photovoltaic Solar: Cost is almost there, but no one has a plan for what to do when the sun isn't shining. Solar systems can only produce energy for about 6 hours a day, which presents a problem when we need energy for 24 hours. It doesn't produce energy during peak demand (~5-9pm) to even help with load balancing. People can currently make a small profit selling back to the grid, but there's virtually no chance of it providing more than about 5% of demand.
Solar Thermal Collectors: Better than photovoltaic as they can generally produce power for about 8 hours, then molten salt batteries can provide energy for another couple; but still not a viable large scale solution.
Wind: Geographically limited, very high maintenance costs.
Hydrogen: Only an energy storage medium, not a means to produce energy. In most cases there are more efficient ways to use the energy directly without the additional loss of producing hydrogen.
Corn Ethanol: Energy storage medium, and a bad one. The most optimistic numbers I've found indicate it requires about .84 gallons of gasoline to produce 1 gallon of ethanol. Most numbers are significantly worse, in the 1.2-1.4 range. It sounds great if the lower numbers are accurate, but 1 gallon of ethanol contains ~2/3 the energy of 1 gallon of gasoline so it's still a net loss. (note: I haven't done any serious research on sugarcane ethanol, which at first glance appears somewhat better)
Hydroelectic: Great technology that is proven, cost effective, and viable; but is severely limited geographically and the dams can cause major environmental concerns.
After years of following the news, studying it, and taking classes in renewable energy; it always comes back to nuclear. If it wasn't for legislative bungling, lawsuits preventing new plants, and the occasional (comparatively) minor failure of 40 year old technology we wouldn't even be talking about a clean energy problem. I'd love for one of these technologies to prove me wrong but there is little indication they will in the near future.
- comicjk 15y agoRe solar PV, the problem of the sun not shining is just a bigger-scale variant of load balancing, which has been addressed successfully before. The English grid does it with pumped hydro storage in this mountain in Wales: http://en.wikipedia.org/wiki/Dinorwig_Power_Station http://en.wikipedia.org/wiki/Dinorwig_Power_Station
- Caerus 15y agoTrue, but the problem is many, many orders of magnitude larger. Looking at US numbers only, we would need to figure a way to store 51.69 TWh and supply over an 18 hour period. They are storing 233 MWh and distributing over 5 minutes. For a pumping station, that works out to 379.4 cubic kilometers of water lifted 50 meters in the air. For comparison, that is 20 times the volume of the Great Salt Lake. About the volume of Lake Erie once inefficiencies are factored in. I also ran the numbers a while back in a renewable energy class for lead acid batteries. That would require something like the entire lead production of the world for several years, just to handle the US.
- semanticist 15y agoYou mean 'the British grid', since if the hydro plant is in Wales it is by definition not English. This is kinda like referring to a project in Texas as Mexican.
- chc 15y agoMore like referring to the USSR as "Russia."
- sliverstorm 15y agoThis has been exactly my conclusion for years now. I am very happy to see someone else so clearly shares my understanding of matters. There's a lot of cool ideas out there, but the tech needs time & research. Classic example is wave power. It gets talked up like crazy; yet many wave power demos produce less than 1W. Yes, I see that you can harvest energy from the ocean- now tell me how that thing is going to power an entire city.