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Comment: Re:Pit stops (Score 3, Interesting) 166

by Smidge204 (#49369193) Attached to: At the Track With Formula E, the First e-Racing Series

The battery is fully integrated into the vehicle and is part of the structure. It can't be easily removed. Not for lack of want, though. Swappable batteries are under development, but it will likely mean compromises in the chassis construction.

I'm more annoyed that there is a *minimum* pit time, meaning drivers have to wait and get penalized if they leave the pits too early.

Comment: Re:Congress is a bunch of fucking retards (Score 5, Informative) 132

by Smidge204 (#49352641) Attached to: GAO Denied Access To Webb Telescope Workers By Northrop Grumman

A really good telescope could as well be turned towards Earth to look at details on the surface.

No. For two reasons:

First, it's an IR telescope. The reason they're putting it in space is to get it away from Earth's atmosphere, which is opaque to the IR wavelengths it's designed to detect. Earth would look like a light bulb for all the IR it gives off and there is zero chance of seeing the surface.

Second, even if it could somehow be used to see through the opaque atmosphere, it couldn't make out anything. The James Webb telescope has a claimed resolution of 0.1 arc-seconds. It's going to be put into the Earth-Sun L2 Lagrangian point, about 1.5 million km from the Earth. At that distance and resolution, each pixel of the image would be ~730 meters square... just under half a mile. Useless for any kind of surveillance.

Comment: Re:We should stop using the word renewable (Score 1) 317

The same can be said for fossil fuel powered generators.

Except that, with the exception of natural gas, you have a lot of other combustion products to deal with. CO2 emissions from cement production are the result of baking the carbon out of the calcium carbonate, and it's relatively pure and therefore easier to deal with.

There are also only ~100 cement plants in the US, versus thousands of fossil power plants.

Where does this number come from? All the articles I have seen put that number at 5% of world CO2 emissions.

-The US produces about 5,500 million metric tons per year of CO2.
-Cement production releases about 1.25 tons CO2 per ton.
-The US produces about 68 million tons (2011) of cement per year.

68*1.25 = 87.5 million tons CO2 per year for cement production. That's 1.5% of the total.

How much does it absorb and what consequences?

33-57% of that which is released during production.

The 0.5 pounds of carbon dioxide equivalent per kilowatt-hour for hydro

Good job cherry picking the worst possible number instead of the one that actually applies. You even went out of your way to quote the article so carefully!

Small run-of-the-river plants emit between 0.01 and 0.03 pounds of carbon dioxide equivalent per kilowatt-hour. Life-cycle emissions from large-scale hydroelectric plants built in semi-arid regions are also modest: approximately 0.06 pounds of carbon dioxide equivalent per kilowatt-hour.

The part you quoted is for tropical zones and peatlands. So how much of the US is in a tropical climate zone, exactly? Hawaii and a little bit of Florida?

Comment: Re:We should stop using the word renewable (Score 1) 317

CO2 generation isn't an impossible challenge. Since the concrete production is centralized, it can be sequestered on site, and concrete naturally re-absorbs that carbon over the decades. Even if you don't address the immediate emissions, since concrete production is a mere 1% or so of total CO2 output by the US and the entire lifecycle emissions (including construction, operation and decommissioning) for hydro is a tenth that of natural gas, you're still coming out way ahead.


Comment: Re:And now why this can not be done in the USofA (Score 1) 317

To US Energy Dept. estimated, in 2012, that there is ~12GW worth of power that could be tapped from existing, non-power-producing dams. That's handily 10% more hydro than what we've got now.

That same report estimates a potential for 65GW of new hydro power installations (85GW if you allow trampling of federal protected lands).

The reason hydro isn't talked about is because of uninformed people like you who think there's no additional capacity.

Comment: Re:Space for solar hasn't been much of a concern (Score 1) 437

It's called spinning reserve, and it's the reason electricity is often so much cheaper at night. Large thermal power plants can take days to shut down and restart, so they need to keep them running anyway.

The problem can be mitigated through various means; and as problems go this is a pretty good one to have.

Storage is the obvious solution. It doesn't even need to be high quality storage, but to reduce over-generation you just need a place to dump the excess energy. You could just dump this energy as heat but optimally you'd want to recover some of it. You don't even need enough storage to carry you through the night, just absorb the over generation and shave peak. Thermal storage would work fine for that, would be relatively inexpensive and could work with existing thermal power plants. Encouraging domestic battery storage, even a few kWh worth, would also help. Almost any existing hydro could be retrofitted for axillary pumped storage.

Less obvious is to tinker with the solar panels themselves, tuning the orientation so you are optimized for late afternoon capture rather than maximum kWh/day generation. That makes the "dip" in the graph shallower and lowers the slope of the ramp.

Retire old plants that are too inflexible to meet variable demand efficiently. In other words, ditch coal.

Add usage penalties (aka "demand charges") during the ramp-up period. There are already demand charges for peak power, but spreading the demand charge out would incentivize energy efficiency and time of use habits.

Basically, there is nothing here that can't be managed with existing technology, but commercial power producers are scared shitless they'll be out of a whole lot of money. Solar is a direct threat to baseline generation (coal and nuclear) as it pushes the usefulness of peak shaving generation (gas turbine) farther into the night hours and makes baseline generation all but obsolete.

Comment: Re:Meanwhile... (Score 5, Interesting) 283

More importantly, this strains the argument that green technologies threaten economic growth. That means dirtier fossil energy is a lot harder to justify, and renewable energy more appealing.

Could be the beginnings of a positive feedback loop. Here's hoping!

Comment: Re:We'll know if its a good bill.. (Score 1) 347

by Smidge204 (#49251499) Attached to: FCC Posts Its 400-Page Net Neutrality Order

They get that money from the normal fees they charge for service.

They do not need to charge an additional fee to "stay in business"

They don't even need to increase their base price if they did away with the itemized fee, because their base price alone is more than enough to cover the cost of business and still make a healthy profit.

How hard is this to understand?

Comment: Re:We'll know if its a good bill.. (Score 1) 347

by Smidge204 (#49249935) Attached to: FCC Posts Its 400-Page Net Neutrality Order

They do not have any money that does not come from their customers, therefore any additional tax or expense (such as the universal access fee) which they have to pay is passed on to their customers.


The fees they normally charge are adequate to cover both the extra cost of the USF contributions *and* their operating costs *and* their investments *and still make a tidy profit.

They can clearly decide not to charge customers for it - which, again, they are not *required* to do which makes the GP a liar.

They do not *need* to, either, since they can still make bank even if they didn't. This is obvious because their *profit* is an order of magnitude greater than their USF contributions. That, consequently, makes you a liar as well.

An inclined plane is a slope up. -- Willard Espy, "An Almanac of Words at Play"