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Comment: Re:Help me out here a little... (Score 1) 483

by Smidge204 (#49505635) Attached to: Utilities Battle Homeowners Over Solar Power

One part of the problem is NOT going to go away however - they have to pay to maintain the lines. Right now, that cost if covered by your electric bills. As the amount of electricity you draw from their generators goes down, they're going to reach the point of needing to charge you a flat fee just for the connection to the power lines, plus the usual fees for actually using their electricity.

For me, the "connection charge" is already an itemized part of the electric bill, so nothing will change.

Smart inverters will solve all of this nonsense. It wasn't long ago that the local gas company would offer special rates to larger customers if they would set up for gas/oil heat and allow their gas service to be remotely shut off. The problem was that, on really cold days, the demand for as would be so high that the pressure would drop and people's furnaces would kick out... so they came up with a scheme that could reduce demand.

I don't see why something similar could not be done with solar. Grid-tie inverters already turn themselves off if they don't "see" grid power that's within the voltage and frequency tolerances, so there is no barrier to getting the inverters to safely shut off or reduce output. All that's needed is a throttling mechanism that will allow the utility to remotely control what goes out into the grid from the home. The inverter can be set to produce only what the home is using and no more, or cut out entirely if needed. We have smart meters that can detect which way the power is flowing so the only missing piece is the control itself.

Seems like a perfect application of power line communication technology; just wedge a controller box in next to the inverter that also interfaces with the meter and waits for a signal to enable throttling.

Comment: Re:incredibly close to target is far from success (Score 1) 340

The mission was complete; the cargo was delivered to the intended orbit with no difficulties.

They just didn't get the bonus points for a successful experiment in first stage recovery. Once first stage recovery becomes routine, then you can consider it part of the operation - but never part of the mission. They are contracted and paid to deliver the payload to orbit, not recover the first stage.

Comment: Re:seem like? No, are. (Score 1) 330

by Smidge204 (#49408881) Attached to: Inexpensive Electric Cars May Arrive Sooner Than You Think

So you're not going to be satisfied until some arbitrary, indefensible requirement is met?

For comparison: The Nissan LEAF alone sold more in its first four years than the Toyota Prius in its first four years. EVs in total have sold roughly a third as many vehicles in four years as the *total* Prius sales in the past eighteen years. (536K[1] vs ~1.4M[2])

I don't think anyone could make a credible argument that the Prius was/is a failure, and EVs are on a trajectory to overcome them in market share despite naysayers, FUD and lack of availability.


Comment: Re:So then where are.. (Score 1) 330

by Smidge204 (#49406035) Attached to: Inexpensive Electric Cars May Arrive Sooner Than You Think

There are no 2-dollar iPhone batteries because you can't (officially) replaces the iPhone's batteries :)

You're also dealing with different types of batteries here. The chemistry used in consumer electronics isn't the same as those used in (most) electric cars... only Tesla uses commodity cells.

An EV battery is also pretty much the equivalent to buying in bulk. If you purchased 500 iPhone batteries (~27kWh worth) at once you might possibly get them for $2 each.

Comment: Re:seem like? No, are. (Score 1) 330

by Smidge204 (#49406007) Attached to: Inexpensive Electric Cars May Arrive Sooner Than You Think

About 3% US market share of similarly-priced vehicles ($25K+) in just 4 years, despite many models being unavailable outside a handful of key states.

That's a far cry from "utter shit" for market penetration of a product that's significantly out of the norm and facing strong opposition.

Comment: Re:Pit stops (Score 3, Interesting) 167

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) 133

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?

Technology is dominated by those who manage what they do not understand.