> Covering the reservoir with a tarp is too expensive (costing over $300 million) and plastic balls are a much cheaper option.
This is what I don't get in this story. How on Earth are plastic balls cheaper than just covering the thing? One would think that a tarp would use less material and be easier to manufacture than the equivalent number of plastic balls.
EDIT: Thanks for all your answers. I guess the heatwaves we have right now in Poland are negatively affecting my imagination :(.
This is what I don't get in this story. How on Earth are plastic balls cheaper than just covering the thing? One would think that a tarp would use less material and be easier to manufacture than the equivalent number of plastic balls.
EDIT: Thanks for all your answers. I guess the heatwaves we have right now in Poland are negatively affecting my imagination :(.