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As much as I support the anti AGW position, I cringe everytime I hear you guys bash 2 things. Solar and Electric cars.
1) Modern solar panels are made out of sand essentially. the chemicals used to make them active is extracted from food dyes. Yes some panels are created in unsustainable ways, but those are becoming the less efficient and more expensive ways.
2) An electric car's propulsion system is ~90% efficient vs a traditional car's 10-25% at best. Yes I know, please hold off the crowing about "yeah but where do the electrons come from?" They come from a plethora of different power plants. About 30% are fossil fuel based.
Now think about that. If electric cars weren't 3 times more efficient than electric cars, they'd still pollute 70% less than a traditional car. Or if we don't ignore the efficiency savings, but power them with coal factories only, (which run at about 80-90% efficiency) they would still be twice as efficient.
i.e.
Traditional car - 100 Units Chemical energy = 20 units Kinetic + 80 Units heat.
That is, it burns 100 units of gasoline, produces ~20 units of kinetic energy and 80 units of heat. (we'll ignore the distribution system's inefficiencies and costs to highlight how wasteful traditional cars are)
Electric car
100 Units Chemical energy = 90 units electricity + 10 units heat
90 Units Electrical Energy = 80 Units of chemical battery energy + 7 units line losses + 3 units heat loss
80 units of chemical battery energy = 75 units electricity + 5 units heat energy
75 units of electrical energy = 70 units of kinetic energy + 5 units heat energy.
That is, 100 units of fossil fuel enters a power plant running at a constant speed, with no limits to efficiency since it's not designed to be mobile or quickly throttle able. it achieves about 90% efficiency, then it's transmitted to your charging station, where there is a 7% line loss and 3% heat loss in storing the power in your battery. Then when you press the accelerator, there is 5 units lost in heat energy where the chemical energy is converted back to electrical energy. Then when the electricity is converted to kinetic, another 5 units are lost.
70 units of kinetic energy vs 20 units.
It's not that electric cars are so good, it's that gasoline engine cars are so horribly inefficient. The only reason gasoline cars, which were invented after electric cars, won out; was that batteries at the time could not compete with the energy density and portability of liquid fuel.
These days, that problem is largely solved, and if the new glass based batteries work out, will surpass gasoline, while using mainly sand in their manufacture.
Oil will remain important as our unsurpassed advanced materials feedstock. It's barbaric imo, that we're squandering most of it simply to burn for heat. That is what I fear we'll be lampooned for in 100 years.
1) Modern solar panels are made out of sand essentially. the chemicals used to make them active is extracted from food dyes. Yes some panels are created in unsustainable ways, but those are becoming the less efficient and more expensive ways.
2) An electric car's propulsion system is ~90% efficient vs a traditional car's 10-25% at best. Yes I know, please hold off the crowing about "yeah but where do the electrons come from?" They come from a plethora of different power plants. About 30% are fossil fuel based.
Now think about that. If electric cars weren't 3 times more efficient than electric cars, they'd still pollute 70% less than a traditional car. Or if we don't ignore the efficiency savings, but power them with coal factories only, (which run at about 80-90% efficiency) they would still be twice as efficient.
i.e.
Traditional car - 100 Units Chemical energy = 20 units Kinetic + 80 Units heat.
That is, it burns 100 units of gasoline, produces ~20 units of kinetic energy and 80 units of heat. (we'll ignore the distribution system's inefficiencies and costs to highlight how wasteful traditional cars are)
Electric car
100 Units Chemical energy = 90 units electricity + 10 units heat
90 Units Electrical Energy = 80 Units of chemical battery energy + 7 units line losses + 3 units heat loss
80 units of chemical battery energy = 75 units electricity + 5 units heat energy
75 units of electrical energy = 70 units of kinetic energy + 5 units heat energy.
That is, 100 units of fossil fuel enters a power plant running at a constant speed, with no limits to efficiency since it's not designed to be mobile or quickly throttle able. it achieves about 90% efficiency, then it's transmitted to your charging station, where there is a 7% line loss and 3% heat loss in storing the power in your battery. Then when you press the accelerator, there is 5 units lost in heat energy where the chemical energy is converted back to electrical energy. Then when the electricity is converted to kinetic, another 5 units are lost.
70 units of kinetic energy vs 20 units.
It's not that electric cars are so good, it's that gasoline engine cars are so horribly inefficient. The only reason gasoline cars, which were invented after electric cars, won out; was that batteries at the time could not compete with the energy density and portability of liquid fuel.
These days, that problem is largely solved, and if the new glass based batteries work out, will surpass gasoline, while using mainly sand in their manufacture.
Oil will remain important as our unsurpassed advanced materials feedstock. It's barbaric imo, that we're squandering most of it simply to burn for heat. That is what I fear we'll be lampooned for in 100 years.
R version- the Energy Return on Investment (EROI) to run a modern industrial society is at least 7 (that is, an input of 1 "unit" of energy to mine, make and use an energy source must yield at least 7 units of energy to make it worthwhile). Solar is nowhere close to 7. And it is intermittent. Try going solar in Edmonton, or Yellowknife in December (I stipulate that, in July you do much, much better in both those places). Solar, in my view, is best used in remote areas where transmission lines are too expensive to run.
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