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Can Wind and/or Solar replace petroleum?

Vehicles in the United States are about 95% dependent on petroleum, with many fueling their flex-fuel vehicles with only petroleum because 1) they have no E85 or comparable reasonably available, and 2) they might not realize what the “Flex-Fuel” emblem on their vehicle means.

Wind and solar energy only generate electricity. Vehicles almost purely consume only petroleum derivatives. The only way to get them to intersect is to add a battery pack to the car.

If you think fuel cells are the way to go, get one of those little fuel cell car kits Edmund Scientific or similar has, with the fuel cell powered by a small battery. Run it via the fuel cell (after depleting the battery), then bypass the whole fuel cell apparatus by powering it with the battery that's supposed to only run the fuel cell (a fresh or recharged one of course). The kit runs much better on just that battery vs. the fuel cell, doesn't it? It's the same for full-size cars.

I've used solar power via $4/watt thin-film panels from Harbor Freight Tools for about four years now in a battery-based (cottage-grade) 12VDC subsystem that via efficiency, conservation and my being the only one living here takes care of about 95% of the energy used for lighting (mostly LED now via DealExtreme $10.61 LED strips), computing (almost purely an Asus eePC900 Linux 12V netbook, some Vista laptop use) and entertainment (a USB-powered amp puts no noticeable load on the system, with occasional 100W car amp use, and no wasting time/energy/money with TV absorption).

My current electric bills, at $0.12 / kWh, range normally from $12 to $15 per month, unless it's a spectacularly rainy month in which case it can reach $22. I offset my consumption via Community Energy wind power ($5/month for 200kWh) and (heating/stove, car, vacations, etc.) for maybe $19/year I think. I looked into residential carbon trading, but I only generate about 1.5 metric tons of carbon per month (1 metric ton = 2205 lbs.), and the minimum unit of carbon trading is a metric ton of carbon, so I'd have to reduce my carbon footprint by 2/3rds to half a minimum unit, which I don't see happening without wrapping my house in an additional foot width of insulation and rebuilding all the doors and windows... Not happening.

My car, a 2000 Honda Insight 5-speed, does have a 1kWh NiMH battery pack, connected to a 13kW motor/generator which itself acts as a rechargeable replacement for a fourth cylinder. I recharge it off the grid when needed via a very simple $100 charger that sits in the little space between the Integrated Power Unit (the portable power station behind the seats) and the fender. Being a hatchback, it gets toasty in the back (where the battery pack is) in bright summer sunshine, so it's better to recharge it at night or early in the morning (mostly off peak hours in other words).

Charging such battery packs (and especially much larger ones of PHEVs, EREVs and BEVs) in off-peak hours would partly use otherwise unused capacity of existing electric power plants, not require additional power plants.

Glossary time:

HEV means Hybrid Electric Vehicle, meaning a vehicle that is strictly liquid-fuel powered that uses a relatively small (1 to 2 kWh) normally NiMH battery pack to act as an energy buffer, absorbing energy mostly during braking, returning the energy under acceleration, and allowing seamless automatic start-stop function at intersections.

PHEV means Plug-in HEV, letting the car use much cheaper (per unit of energy provided) grid-sourced electricity instead of refined petroleum partly from nations who use our oil payments partly to fund religious extremism and terrorism. PHEVs are typically suffixed with their mile range: PHEV-40 means a 40 mile battery-provided range before the gas engine kicks in, such as the upcoming Volt with its 16kWh battery pack. My 2000 Insight with its little hand-crafted charger and 1kWh pack would be called a PHEV-2, since folks with Manual IMA have found it can go 2 miles of battery power alone.

EREV means Extended Range Electric Vehicle, essentially a battery-powered car that also includes an integral liquid-fueled generator who sole function is to keep the battery pack out of excessive discharge in extended trips. That is an exact description of the Volt's operation, “battery first, then gas”, with the gas only being used to generate electricity, no internal combustion engine mechanical linkage to the wheels.

BEV means Battery Electric Vehicle, a pure battery-powered electric car like the existing Tesla Roadster and the upcoming Nissan Leaf with its air-cooled pack (the Volt's and Roadster's are liquid-cooled) and 220 and 100 mile ranges respectively. It also includes the early EV-1 Impact of “Who Killed the Electric Car?” fame, and the very early Baker Electric and similar lead-acid -powered vehicles from before any gas-powered cars had electric starters. If your vehicle use is within your BEV's range, you carry no deadweight in the form of an unused internal combustion engine and all the associated noisy, vibrating, grimy, hot bits that go with it. But if you run out of charge, it will slow to a stop. Like gas-powered cars, they of course require refueling too, in their own way, and while each refueling costs less for what it does, the energy stored in a battery pack, per pound, is a small fraction of the energy stored per pound in a full gas tank.

One last final tidbit regarding xEV transmissions: Electric motors' torque, the twisting force they put on their axles, is proportional to the current that goes through the motor. Because they try to send an opposing current back with a force that is proportional to the motor's speed, their torque is great only at low rpm. Since that's where they soak up the most current, hard low-rpm use depletes the battery pack the quickest, making life hardest for the electronics and battery pack powering them, and it's where efficiency is the lowest. (But it's conveniently also where vehicles need serious torque the most.) The Tesla Roadster started with a 2-speed transmission so initial launch would be easier on the motor-driving electronics, but then went with a much simpler and lighter single-speed tranny when it improved the current-carrying ability of that electronics. Home-brew EV conversions using the original transmissions get their best range when kept in 1st gear, but you need a motor and transmission with a very wide rpm range (i.e. 0 – 8000+ rpm, all tolerant of truck-grade low-rpm torque). A 3-speed tranny that let the motor hit redline at say 40 mph would really conserve battery power around town while easily making tire-shredding pull-away power, but would add cost-adding complexity, weight and reliability issues vs. a straightforward single-speed gearset.

Solar energy is generated the most during peak consumption hours, but costs more than wind turbines per watt-hour generated. So its intermittent nature requires less buffering by natural gas -powered “spinning reserves” and/or large stationary industrial-scale battery stations.

Wind, on the other hand, costs the least of renewable energy sources but tends to produce more at night. So if you go mostly with wind power, you have a serious need to buffer it via significant added spinning reserves and/or battery stations.

This is where plug-in vehicles come in. Plugged in at night to recharge, they help soak up surplus generation, and when plugged in during peak hours, they can act as distributed spinning reserves/battery stations by leveling out electrical loads faced by the grid. They are the perfect compliment to naturally fluctuating solar and especially wind -powered electricity sources, as long as the grid can communicate with their two-way chargers. That communication is what the “smart grid” is all about, and that communication would allow xEV owners to get money back from the electric utility companies based on their vehicles helping with electrical load leveling.

Why does Obama keep seeming to push nuclear energy?

Coal-powered electric power plants are considered “base load” plants, meaning they generate most of the nation's used electricity but aren't expected to rapidly power up and down to try to match real-time power demands (that's what “spinning reserves” are for short-term, and medium-response “standby reserves” are also for). Coal is however essentially pure carbon with some goodies like sulfur, mercury and arsenic in it too, so it's the most polluting fuel available. The only other base-load generation technology available is nuclear fission, which isn't expected to deviate from 100% operating capacity without lots of paperwork being passed around well ahead of time.

Hydroelectric power plants are a different thing, with power outputs that change only with seasonal or yearly rainfall / snowmelt changes. They can however alter output with standby reserve -grade speed, and even act as a battery in some places, pumping water from a lower reservoir back up into the main upper lake / reservoir but with limited efficiency.

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