wcalvin’s Recent Comments

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  compressed air from the wind turbine?

  Forgot to add that one could always design the system from scratch so that the windmills simply compressed air to add to the underground cavern, that electricity generation then ran 24/7 off the compressed air.

  Works just like a spinning wheel: foot taps are converted into smooth rotary motion.

  Anyone ever heard of such a design?
  On Renewables are pulling two directions, nationwide and local posted 1 year, 11 months ago 39 Responses

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  inherently unstable AC grids

      Some carbon-free electricity sources have serious drawbacks when scaled up too fast. That's because the power grids themselves are already unstable, as frequent power outages remind us. That they don't happen more often is only because most sources and loads are predictable. When unpredictable wind and solar power is added to the balancing act, network outages become more likely.
      The current projection for growth in wind has it replacing 5 percent of fossil fuels by 2020 and that may be as fast as we should go unless we use energy storage such as a flywheel or an underground reservoir for compressed air. Some cities in Iowa are planning a 100 megawatt wind farm with 200 megawatts stored underground as compressed air.
  [More in chapter 19 of my Global Fever: How to Treat Climate Change.]
  On Renewables are pulling two directions, nationwide and local posted 1 year, 11 months ago 39 Responses

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  Irreversible aspects of global warming

  Ask him about ice sheets becoming unstuck by melt water ponds draining to bedrock and greasing the skids.

  Once the water gets trapped under the ice sheet, it can seldom refreeze as that would require expanding and the pressure is too great for that. So you get a cushion of water building up under the ice sheet. "Ice quakes" occur because the rough bedrock surface causes the glaciers to stick; they only accelerate when enough hydraulic pressure has built up to help float the glacier over the bumps.

  So that aspect of global warming is, alas, irreversible. Even some cooler decades afforded by less heat from the sun wouldn't undo this instability, though it would prevent additional outlet glaciers from becoming unstuck. Greenland was once 5F warmer and it melted enough to raise sea levels 4-5 meters all by itself. And 5F is on the low end of estimates for 2100.On Me and Al Gore posted 3 years, 6 months ago 25 Responses