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Comment: Re:Not Actually $3500 (Score 1) 309

by Smidge204 (#49615795) Attached to: Tesla's Household Battery: Costs, Prices, and Tradeoffs

Burning natural gas, aka heat, is not a "higher grade" energy than electricity, it's a lower grade energy. Electricity can be converted losslessly into heat. Turning heat into electricity loses a large chunk of it.

Natural gas can be converted into heat too, with staggering efficiency. Nearly perfect efficiency, actually! It's in transferring that heat into the thing/substance you want heated that the losses are incurred; but a good condensing boiler can easily put 98% of the energy stored in natural gas into the water that it's heating.

So really, if the metric (that we seem to agree on) that determines "quality" of energy is how efficiently it can be converted to something else, Natural Gas is pretty damn good.
=Smidge=

Comment: Re:Not Actually $3500 (Score 3, Informative) 309

by Smidge204 (#49610023) Attached to: Tesla's Household Battery: Costs, Prices, and Tradeoffs

It's not an idiotic waste of energy if:

1) The energy would otherwise come from other, equally high grade (or even higher grade) energy sources, e.g. natural gas

2) The energy would otherwise come from non-renewable sources, e.g. natural gas

3) The energy would otherwise not be used at all due to overproduction

The monetary value of electricity flowing back into the grid on net metering is extremely low - much lower than the cost to purchase that electricity from the grid. If you have a choice between selling the power to the grid or using it to "generate low grade heat" with an electric stove, then the stove wins just on financial grounds.

If your argument is that you could use direct solar thermal methods to generate that heat - skipping the conversion to electricity - then sure it would be more efficient that way. When the source of energy is free, however, and you have already invested in the infrastructure for other reasons, it makes perfect sense to utilize solar electricity for cooking and cleaning. The alternative is to invest even more on additional infrastructure to utilize the same free energy source in a moderately more efficient way.

Use it or lose it, as they say.
=Smidge=

Comment: Re:Far too expensive for a used car (Score 3, Informative) 65

by Smidge204 (#49607349) Attached to: Tesla Adds Used Models To Its Inventory, For Online Purchase

From owner's estimations, ~90% of the battery's stated capacity is actually available for use. The 10% is not so much "fail-over" capacity as it is a buffer to keep the battery away from the extremes of charge/discharge states, where most of the degradation occurs.

Your cell phone battery has no problems charging to 100%, since you want to get as much energy (and therefore use time) in there as possible for the weight. However, charging to 100% harms the chemistry, and after a few years the battery no longer lasts as long. That's fine for a cell phone - part of it is planned obsolescence, part of it is the reality that a lot of people won't keep their phone more than a few years.

In an EV you have the luxury of maintaining a charge buffer, since the added weight and cost is fairly minimal and people have a much higher expectation of long-term performance.

So usage pattern + design (thermal management) + energy management which does prevent the user from destroying it = significantly different performance degradation profile.
=Smidge=

Comment: Re:This is about money (Score 1) 314

by Smidge204 (#49573499) Attached to: Feds Say It's Time To Cut Back On Fluoride In Drinking Water

"There is no viable evidence" = "I'm too lazy to look"

http://www.ncbi.nlm.nih.gov/pu... (Free)
http://www.ncbi.nlm.nih.gov/pu... (Non-free but synopsis provided)
http://www.ncbi.nlm.nih.gov/pu... (Non-free but synopsis provided)

And that's just a minute or two of looking. Thousands of studies have been done on fluoride for safety and effectiveness on a wide range of topics, not just public water fluorination. It works, we know how and why it works, it's pretty dang cheap, and it's been hailed as one of the top ten greatest public health achievements.
=Smidge=

Comment: Re:I love KSP, but sometimes... (Score 1) 99

by Smidge204 (#49570377) Attached to: Kerbal Space Program 1.0 Released After 4 Years of Development

You might be over-estimating the effect heat actually has, the actual sources of heat or the rate at which it builds up.

I know i haven't had sufficient opportunity to test things out for myself yet, but it really does not seem like heat is really a factor outside of atmospheric effects.
=Smidge=

Comment: Re:This is about money (Score 2) 314

by Smidge204 (#49568843) Attached to: Feds Say It's Time To Cut Back On Fluoride In Drinking Water

Too much fluoride causes tooth discoloration (fluorosis). It's harmless but unsightly.

But that aside, I wonder what's less expensive: Fluoridation programs, or dental treatment for the extra problems that would arise from stopping fluoridation. That would be an interesting study to thumb through...
=Smidge=

Comment: Re:I love KSP, but sometimes... (Score 4, Informative) 99

by Smidge204 (#49568057) Attached to: Kerbal Space Program 1.0 Released After 4 Years of Development

But, in typical Squad fashion, they gave us the ability to overheat - but failed to give us the ability to cool off.

Parts act as blackbody radiators and will cool off just like any object would.

Solar panels also now act as passive radiators (source) so they now have dual functionality.

They also gave us a more advanced (and accurate) aerodynamics and engine performance model - but at the cost of the game's much vaunted simplicity and user friendliness.

I dare say the new model makes it *easier* to get a rocket or space plane flying. Too easy, actually... my rockets and planes from 0.90 are all way too fast and destroy themselves much faster than they used to. I haven't had time to really dig into the new mechanics but so far it's promising that my 2000+ ton rockets might actually fair better than before!
=Smidge=

Comment: Re:Curse you, Entropy! (Score 1) 483

Thermodynamics

...means nothing with respect to carbon emissions.

In contrast, using the "renewable energy source" directly yields much higher net benefit.

Only for certain values of "benefit."

Liquid fuels are extremely energy-dense, portable and stable. Yes, you might trade total net energy for that benefit, but that's not a deal breaker if the energy is extremely cheap (renewable). You can have battery powered cars (of which I'm a major proponent), even battery powered/hybrid trucks. You're not going to have a battery operated cargo plane any time soon, nor an all-electric cargo ship, and I can't imagine a battery powered rocket.

Then there's transport. You can put liquid fuels on a truck or train car, or on a boat, and transport it anywhere. You can even use a pipe: A 6" pipe carrying diesel fuel can transport as much power as the entire output of a large nuclear power plant (~1.8GW).

The density and portability of liquid fuels is a HUGE benefit and worth paying the energy price for in many circumstances.
=Smidge=

Comment: Re:Curse you, Entropy! (Score 1) 483

All well and good, but doesn't exactly solve the problem of greenhouse gas emissions.

Sure it does; you'd be extracting this carbon out of the air, or from a process stream that would otherwise dump to the atmosphere. Best case you have a net zero carbon emission, worst case you're using the same carbon twice (industrial waste stream to vehicle fuel to emissions) which is still a significant reduction.

Plus it cuts down on other pollutants, eliminates the environmental damage from oil extraction itself, eliminates emissions from the refining process and possibly reduces transport energy costs.

They just need to scale it up... easier said than done, of course.
=Smidge=

Comment: Re:Progressive Fix 101 (Score 3, Interesting) 622

by Smidge204 (#49529915) Attached to: Cheap Gas Fuels Switch From Electric Cars To SUVs

None of these vehicles have a substantial impact on roads, though. Heavy trucking accounts for the vast majority of road wear.

That said, I have no problem with paying to help maintain the roads even if my contribution to their wear is practically nonexistent. I benefit from our highway infrastructure because even if I never drive on them, I almost certainly use products and commodities that are transported over them.

Keep the gas tax, maybe even increase it, to pay for the problems that fossil fuel consumption causes.

Add a new, independent road maintenance fee that's based on vehicle weight and miles driven.
=Smidge=

Comment: Re:Help me out here a little... (Score 1) 533

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.
=Smidge=

Comment: Re:incredibly close to target is far from success (Score 1) 342

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.
=Smidge=

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