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Yes. OTOH, a lot of power is lost during transport from the central plant to the consuming device.

Score 4, Insightful? Sorry, but electricity transmission in the US averages 92.8% efficient.

anything else is just shifting from local pollution to remote pollution

Making pollution more remote *is* a good thing. Many pollutants have relatively short atmospheric lifespans. The further they are from people on average and the higher altitude they're emitted at, the better. Furthermore, power plants are more efficient than ICEs. And they have big, central scrubbers. And only half of our power in the US is coal (less elsewhere); the next leading sources are nuclear, natural gas, hydro, and wind. And coal's share is falling.

No, that stat is for the efficiency of the entire T&D system.

False. Transmission is efficient -- in the US, an average of 92.8% efficiency.

I do know that actually. But transmission and distribution losses in the USA are estimated at 7.2%. If the longest feasable power line is 4000 miles long, and google is putting their data centers 4 miles from hydro electric plants, they're saving 7.2% more energy than other data centers on average (margin of error 0.001%).
 
Transmission losses are one of the biggest arguments in heating the home with gas vs. electric, since with gas you're getting 100% of the avalible heat from the fuel, as opposed to electric where at most 90% of the heat is converted into electricity at the plant, you lose another 7% in transmission and then another 1-2% in the heater itself = 18-19% energy loss from a coal or natural gas power plant vs. heating with gas in the home.

Where I live, more than half the cost of electric is in the delivery/line charge.

It doesn't matter how much is in the "delivery line charge"; cost does not equal efficiency. In the US, the average transmission efficiency is 92.8%.

you lose 15% in the charger

AC Propulsion's 20kW charger is 93% efficient, while their 150kW charger is 90% efficient. That's pretty typical for non-inductive chargers.

and another 30% to the lead acid battery.

Lead-acid battery? Lol, what do you think we're talking about here, golf carts? NEVs? Even Firefly lead acid batteries are simply unsuitable for these sort of tasks. Way too short lifespan, way to inefficient, way too low energy density. We're talking about lithium ion variants. Lithium ion batteries are over 99% efficient (that's why they charge and discharge cool).

So while at the power plant rock in efficiency, it doubles in cost getting to my house

Please learn to separate the concepts of "cost" and "efficiency".

My understanding is Gas engine are 70-80% efficient

Try about 20%, give or take.

It's okay to be unfamiliar with this topic. Just educate yourself so you're more informed for future debates and we can talk some more. :)

Wind, water, and solar plants may have low efficiency for turning energy into electricity, but the energy required to do that is free, unlimited, and does not directly pollute, so therefore is irrelevent.

Wrong. *Nothing* is irrelevant. Wind and solar have huge capital costs relating to all of the mining, processing, and labor that goes into them. Think giant towers of steep pop out of the ground without extensive mining and very dirty smelting operations, for example? The environmental cost of wind and solar is certainly notably lower than coal, but it *is* relevant. They also take up land that could otherwise be wilderness (especially solar, which can't pair with farming like wind can).

Hydro ("water") is the worst. It takes up huge amounts of land -- often ten times as much as the equivalent amount for solar generation in a sunny location. It destroys what are often some of the most scenic and environmentally sensitive areas in a country. Consider the Xolorado, for example -- an aquatic oasis in the middle of arid lands that used to even have otters living in it before we dammed the heck out of it and destroyed canyon after beautiful canyon. And to top it all off, *hydro causes global warming*. Hydroelectric plants lead to organic matter decaying anerobically instead of aerobically, which means methane, not CO2. Methane is a far worse greenhouse gas than CO2.

Efficiency ALWAYS matters.

I'm NEVER going to suggest we use coal or other fuel to compress the air for air cars, nor would I for electric cars either

It's better for the environment to run an electric car from coal electricity than a gasoline car burning gasoline. By a good margin. It's notably *worse* to run an air car from coal power.

The direct efficincy of stored energy to engine power is near 100% for air cars.

~90% or so. It's getting the energy stored that's the problem -- 10-15% efficiency from garage or onboard-scale compressors.

Your numbers on electric motor efficiency are also WAY off. Yes, motors can operate at those efficienies, but only under constant and predictable (ideal) torque and RPM. In the field, they almost never come near those ideals. They do much better (60% or so efficiency for electric

Sorry to be blunt, but you simply have no clue what you're talking about. Start reading. The most efficient electric motors are about 95% efficient. 85-90% is more typical for an electric car in standard driving conditions.

combine this with distance loss of poewr over high voltage lines

A) Air compressors have the exact same loss.
B) Once again, you demonstrate your ignorance. In the US, transmission losses are only 7.2%.

battery charge loss (heat when charging)

0.1% for li-ion.

battery depreciation (loss over time)

Virtually none with modern automotive li-ions (nanophosphates, titanates, spinels, etc).

and discharge loss (bettery efficincy)

Also 0.1% (see above link).

the other problems with electric cars are safety

That's funny coming from an air car advocate, given that compressed air has the fastest energy discharge in disaster conditions, faster than even hydrogen.

LiIon batteries explode

Automotive li-ions (titanates, nanophosphates, spinels, etc) do not.

capacitors can kill instantly

So can an exploding air tank. Both are "accident situations", but the former requires either new laws of physics or the casing to break and move out of the way, all of the engine components between it and you to move away, terminals to suddenly run into you or something you're sitting on, all without the fuses melting.

they're complex and expensiv

Sure. Lets take a natural gas furnace as an example.

The one in my house is 90%+ AFUE (Trane XV90). That means that, according to Trane and ASHRAE Standard 103 at least, 90% of the available heat energy in one unit of natrual gas is transferred into my home.

Using our previous measure of the COP 1.0 resistive heating element, that one unit of fuel is used far less efficiently to heat your home because of the losses involved in converting it to electrical energy and back to heat.

A few miles from my house there is a natural gas fired demand power plant. It's one of the most efficient around, since it's a hybrid gas turbine engine + steam turbine plant (the exhaust from the gas turbine heats water which powers a steam turbine). Its peak efficiency is around 50%. Then the power is transformed from generation voltages to transmission voltages, sent across transmission lines, transformed at a substation back to distribution voltages, then transformed in front of my house to consumable voltage levels. This combines for a loss of about 7.2% according to the DOE http://climatetechnology.gov/library/2003/tech-opt ions/tech-options-1-3-2.pdf.

So that energy from one unit of natural gas my furnace converted to heat at 90% has now become 1 Unit * 50% (generation efficiency) * 92.8% (transmission efficiency) * 1.00 (conversion to heat by resistive heating element) = 46.4% efficient.

But, the furnace heats my entire house, not the one room I'm sitting in, so your point is valid -- it's best only to heat the space you're using at any given time. My contention is that with our current technologies and power distribution systems, there are more efficient ways to bring heat into a room than with lamps. This is particularly true at night when I don't want all the lights on.

Compact flourescents aren't for everyone. We use them in every room in our home except one closet, but we chose bulbs with good color temperatures and selected our paint colors under that light so it looks correct. But then, we try to be as efficient as possible with our power and gas use; not because we believe in all the current environmentalism hype and trends (I don't), but because I am conservation minded and hate writing big checks to the utility companies.

The carbon generated by burning biofuels was sequestered by the plants that made the biofuels. And will be resequestered by the same plants. The idea here is that, since we have to grow enough crops to produce enough fuel, that it becomes a carbon cycle rather than dumping carbon that's been sequestered for centuries back into the atmosphere.

Meanwhile, iron fertilization seems to be a good solution to the problem of the excess carbon we've produced in the past century.

The biggest problem of any Lunar undertaking is water, or more appropriately, hydrogen, as there's loads of Oxygen.

Now, what if there just isn't that much ice in those lunar polar craters. AFAIK, there's only speculation that there may be ice there, but nothing has been proven, has it? The data is inconclusive at the moment. And even if there is ice there, there seems to be good amount of evidence that it will not be all that much, ranging from one small lake to a "sea" the size of Connecticut.

A lot of industrial processes need water in large quantities and this may prove to be exhaustive of what little lunar ice there may be. In other words, lunar industry for water and rocket fuel might just deplete the moon's natural resources as fast as our need for oil does.

If this worst case scenario turns out to be true, what would possible solutions be? Would it be realistic to smash an ice asteroid into the moon? I don't think we are quite capable of that just yet.

What about artificially creating hydrogen as a by product of nuclear fission or some such process that strips a proton off an atom? According to a quick Google search, it is quite possible with today's technology and there seems to be quite a lot of Uranium on the moon as opposed to hydrogen.

I think that artificially generating hydrogen might actually make a lunar base more flexible with respect to positioning, although placing the base in a polar crater might help to shield it from Solar eruptions and meteor impacts.

Clean Energy Systems paper

Carbon Capture and Storage from Fossil Fuel Use

Capturing and sequestering carbon dioxide"