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Comments · 6
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Live like Europeans
What I think many of the "Just use less" people really want is a complete change of lifestyles.
Not unless you think the lifestyles of Europeans are completely different from those of Americans. Having lived in both regions, I can tell you they're not that different, despite rich-country Europeans using half the energy per capita that Americans do.
Plus walking - or waddling - around town would do many of us a lot of good.
It's easy to say "Just use less", but to get to the point where you can use less sometimes requires some economically UNviable steps, like those I mentioned above.
Which part of "insulate your house and buy an efficient heat source" is not economically viable? In most cases, it'd pay for itself due to energy savings in 4-8 years.
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Re:The electric car you want is ready now:
If you travel less than 50 miles a day you should look into buying a bicycle.
Oh sure. 4 hours brisk cycling (in all weathers) is what everyone needs to add to their daily routine. I often cycle to work which is a 27 mile roundtrip, but I sure as hell wouldn't want it to be any further, and I'm not doing it unless the weather's good.
Mind you - 50 miles driving from a 1 square metre solar panel. Really? Available energy at the earth's surface is about 1kW/m2. Photovoltaic cells are about 10% efficient so that's 0.1kW/m2. That means that after 8 hours of direct sun you've got 0.8kWh to play with. I strongly suspect that you're not going to move a full size car 50 miles on 0.8kWh...
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Re:Oil not equal to nuclear
That's dumb. As dirty as coal plants are, they are far cleaner than the equivalent power output from internal combustion engines.
Wrong. Energy efficiency of a coal power plant is roughly 10,000 BTU of heat to produce 1 kWh of electricity, which works out to about 34% (1). Factor in about 93% efficiency for electrical transmission (2), 85% battery storage efficiency (3), and 90% electrical-to-mechanical energy conversion efficiency for electric motors, and the whole path from coal energy in to mechanical energy out works out to about 24% efficiency.
In comparison, an internal combustion engine is roughly 25% efficient from gasoline energy in to mechanical energy out (4). So it's really a wash.
In the end, the decision comes down to other factors, like weight of engine and energy storage systems, cost, and available infrastructure. By all means, make IC engines more efficient, but it's crazy to throw them out at the moment.
In a time of unlimited options, the world chose gasoline as the perfect transportation fuel, due to its power-to-weight ratio, efficiency, simplicity, portability, and storability. As energy becomes scarcer, let's reserve it for the job it's best suited for.
(1) http://www.doe.gov.ph/EE/HRIPP.htm
(2) http://www.canren.gc.ca/prod_serv/index.asp?CaId=101&PgId=550
(3) http://www.ceere.org/iac/assessment%20tool/ARC2410.html
(4) http://en.wikipedia.org/wiki/Engine_efficiency -
Re:Canada?
"During the winter months, it probably gets less than 10 hours of sunlight a day."
What part of Canada are you talking about? You do know that Southern Ontario, where a third of the Canada's population lives, is at the same latitude as Southern Oregon and Northern California right?
The "not enough sunlight" argument is a myth anyway.
http://www.canren.gc.ca/prod_serv/index.asp?CaId=1 01&PgId=573 -
Re:Cost?
Does any one know how much they spend researching, designing, and building this?
I've seen amounts of about $1 million/MW. Adjust the currencies, and these two sites give roughly similar estimates.
Design costs go down with economies of scale, just as research and financing. For more background info, I suggest the Earth Institute's briefing. Their data sheet is quite interesting- it really illustrates how fast costs have been going down.
There should be no doubt that this will be an important source of energy in the future. -
Re:But the question is the costFor cold places, a more cost-efficient use of solar energy is for solar heating. Efficiency of around 70% can be achieved, giving low-grade heat which can be used to pre-heat air or water for a heating system. While a traditional heating system is still needed to bring the temperature up to desired levels, less fuel is needed to maintain the same temperature. At a GM battery plant in Oshawa, Ontario, such a system generated 455 kWh/m of solar energy per year, representing a contribution of 317 MWh annually. This is a savings of between $4,700 and $12,200 depending on the fuel used for traditional heating (1991 prices, CAD$).
Similar technology is being used in car-washes to pre-heat water. I wonder if the flexible material technology could be incorporated into a system that pre-heats in the winter, and in the summer generates electricity which could be used for cooling. The summer months have some of the highest electrical energy demands as air conditioners are running.
I would imagine that you might be able to reduce the heat incident on the building using this material in the summer. For example, instead of introducing the heated air into the building, you could vent it out the top using either convection or wind-powered turbines.
Solar heating seems like a great alternative. Our house has good southern exposure, and stays reasonably warm during the day even with the heat set low (10C). Right now it is about 19C while it is -22C outside (-7F).
Photo-voltaics may also be useful, but the parent comment's points are quite good explanations for why they aren't in widespread use. On the other hand, if the cost of installing a system is sufficiently low and the esthetic is good enough, this could be a reason for buildings like warehouses and so on to reduce their reliance on non-renewable energy.