I am not sure how rare Earth mines are set-up, but this does seem to be a disadvantage to using hybrid vehicles. When the electricity is produced from coal, I wonder how much less CO2 emissions are produced anyways? Anyone know a way to find out?
This is one of the main issues with hybrids/electric vehicles. They still rely on non-renewable resources as a source of "fuel". Look up research on lithium, one of elements commonly used in rechargeable batteries.
In response to your question Koel:
In Alberta (with a mix of natural gas, hydro, wind, and coal generation) for every GWh of electricity generated, 884 tonnes of CO2e are produced.
Ok, but how many watts are used per Km? Would the CO2 used be more than if gasoline (or ethanol) was used? Basically I want to know if it is worthwhile to mine these rare metals, or if the reduction in CO2 is marginal.
One very promising aspect to ethanol production:
There are some initial reports that peg switch grass at negative CO2 balance - meaning that it actually takes CO2 out of the atmosphere. It does this by storing extra carbon into the soil when it grows. The reports also assume that waste or biomass is used at heat energy to distill the ethanol, but that is to me what sustainable design is all about. Unfortunately it will be a few years before they determine if switch grass is commercially feasible. The major study ongoing is in the Oklahoma panhandle - and a commercial plant is scheduled to be built in nearby Kansas just as the study is completed in the end of 2011.
A new plug-in hybrid electric vehicle coming onto the market is the Chevy Volt. Chevy claims that it can go 40km on one charge (8.8kWh for full charge). Lets use this vehicle as an example.
884t CO2e/GWh = 884,000kgCO2e/GWh = 0.884kgCO2e/KWh
0.884kgCO2* 8.8kWh = 7.7kgCO2 per 40 km.
7.7kgCO2/40 km = 0.19kgCO2/km =19gCO2/km
There is 2360g of CO2/L of gasoline
A fuel efficient internal combustion vehicle = 6.0L/100km = 0.06L/km
0.06L/km* 2360C02/L= 141.6g CO2/km
plug-in hybrid electric: 19g CO2/km
fuel efficient vehicle: 142g CO2/km
There are also criteria pollutants from combustion of gasoline that should be considered such as NOx, PMs, and ozone etc. For combustion of coal, there is Hg, NOx, SOX, PMs etc. I have read a couple papers that modeled air quality based upon number of plug-in electric vehicles within an urban area. Results showed that air quality improved within urban areas, and not surprising, (air quality) decreased around coal-fired plants as the result of increased generation.
There are also the economic and infrastructure related issues surrounding electric vehicles, but that is another can of worms.
Considering most cars on the road don't get even close to 6.0L/100km (mine is more like 8.5L/100km and it is a small fairly fuel efficient car) the hybrid vehicles are easily 10 times more efficient. What the problem then moves to is the reduced air quality around coal plants. With more sustainable electricity production hybrids look great - but it's too bad the metals are so rare and contribute to environmental damage in those areas as well.
The first algae-fueled vehicle called the 'Algaeus' has begun its drive across the country.
What a poor name. Not sure what would be better, but com'on Algaeus?