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Comment: Re:OK (Score 1) 268

by compro01 (#47991023) Attached to: IBM Solar Concentrator Can Produce12kW/day, Clean Water, and AC

They are doing some funny math to claim 80% efficiency, as that is almost double the current best efficiency achieved in a lab:

And I'm pretty sure 80% efficiency is above the theoretical maximum too . . . .

Nothing funny about it. This thing is combined heat and power system. You get electricity directly from the cells, and in keeping the cells cool, you get hot water suitable for running an absorption chiller and desalinating.

Comment: Re: Not just Reno (Score 1) 444

by compro01 (#47900385) Attached to: If Tesla Can Run Its Gigafactory On 100% Renewables, Why Can't Others?

its just a simple idea I have always considered; loading electrical energy into physical potential energy by way of working against gravity. Maybe, instead, just run a big heavy chunk of metal up a notched pole? Then release it to spin a worm gear, to a large cog, then big generator as it slowly drops?

You'd still have the exact same issue with the amount of mass and/or height needed. Mass x height x 9.8m/s^2. For a kilowatt-hour of storage, mass x height needs to equal about 600,000. Gravity-based energy storage simply requires a lot of both for any worthwhile amount of energy.

Comment: Re:Credit System (Score 2) 444

by compro01 (#47887881) Attached to: If Tesla Can Run Its Gigafactory On 100% Renewables, Why Can't Others?

Banks of batteries are expensive and take up a lot of space. You'd need to provide several megawatts for several hours. That would require hundreds of 85kWh car battery packs.

And they'll be producing several hundred thousand such packs annually once the factory is operational.

Also, it's going to be a 10 million square-foot facility, with a few hundred more empty acres around it. I don't think they'll be pressed for space.

Comment: Re:Okay... and? (Score 1) 316

by compro01 (#47740247) Attached to: For Microsoft, $93B Abroad Means Avoiding $30B Tax Hit

That's very much incorrect. It's treated as a deduction

Read the site.

If you paid or accrued foreign taxes to a foreign country on foreign source income and are subject to U.S. tax on the same income, you may be able to take either a credit or an itemized deduction for those taxes.

You're assuming it is always option 2 (acts as a deduction), and ignoring option 1 (acts as a credit).

Thus spake the master programmer: "After three days without programming, life becomes meaningless." -- Geoffrey James, "The Tao of Programming"