| ??? 03/26/10 19:40 Read: times |
#174537 - ITER is supposed to reach 1:10 Responding to: ???'s previous message |
Per Westermark said:
One open issue is still what the cost will be for magnetic flasks to encapsulate the reacting materia. And how much energy will be needed, in relation to produced energy to confine the core? Such questions are very important when discussing possible and/or practical sizes. ITER is supposed to reach an energy multiplication factor of 1:10, i.e. for each unit of energy spent confining and heating the plasma they will harvest ten units of energy in the form of radiation. And if it's local, then it isn't really a problem? It is a technical problem that every heat-based power plant faces. It has little (nothing) to do with global warming. With 33% total efficiency, a 500MW power plant would not only produce 500MW of electricity but also 1GW of heat. If sent out into a river or the sea, that heat will add "on top of" the normal heat and can lead to environmental changes for several kilometers. I'm not convinced that it would be much better to use huge cooling towers boiling off a lot of water. If built close enough to a city, the waste heat could be used for heating. And, well, basically any large heat-based power plant dumps several gigawatts of heat into the environment, somehow. So in the end, you still need to think about both the global warming (which is a question of heat retention), and the extra heat produced by the power plant. If you use fusion power plants to _replace_ coal-, oil- and gas-burning power plants, you'll slow down or even eliminate AGW. |
