I was reading about the 10 most fuel efficient cars this morning and what lacked in the descriptions was the cost of energy to operate these vehicles. The claims of excellent gas mileage is one thing but there were no accounts of the cost of electricity when recharging hybrid cars. Has anybody seen an analysis of energy cost of a hybrid car versus a comparable sized gasoline and diesel car?
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Energy Cost of a Hybrid Car
- Thread starter chicopee
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SomptingGuy
Automotive
With or without tax, which (currently) dominates gasoline & diesel fuel prices?
- Steve
- Steve
j2bprometheus
Mechanical
In the US, the price of electricity varies significantly from region to region. Residential customers generally pay a fixed rate per Kilowatt-hour, regardless of when they consume the electricity.
So doing the analysis for a range of electricity prices would be helpful.
Another helpful analysis is to assume various prices per gallon of gasoline (or diesel fuel) and calculate how long it would take for the fuel savings to make up for the higher initial cost of a hybrid vehicle compared to a conventional small car.
I thought you were going somewhere else with this - the energy cost of producing the batteries and what-not. You could probably try to estimate that off of the base price of the vehicle (factors like engineering cost would be difficult to analyze - but for a late generation vehicle like the Prius could be assumed to be somewhat lower).
As for your question:
Most hybrids do not use plug-in energy, so the fuel mileage is directly comparable. For those that do - remember that plug-in energy is generated from the cheapest stationary source available, is generated in great bulk, and for the most part can be generated from an optimized system (meeting peak demand in the face of all the AC units in LA kicking on simultaneously excepted). We should probably expect that electric is cheaper even though it has to be converted and transmitted.
The cost of electricity generally runs 8 to 25 cents per kWH (you can find even cheaper examples than 8 cents). By contrast, a gallon of gasoline has about 34 kWH of fuel energy which a great car will realize about 10.5 kWH of actual motion energy from. From the plug to the wheel, 80% realization of electricity to motion is not a bad estimate - upstream inefficiencies in electrical generation are accounted for in the kWH price.
The true cost of gasoline is about the pump minus 55 cents or so in most states (including federal and state fuel taxes). You can also figure from the barrel price with a markup for refining and distribution. At today's prices, that puts a gallon of gas at, very roughly, $2 of real cost, or 19 cents per kWH realized motion energy. Electricity by the above estimates comes out to a range of about 10 cents to 31 cents per kWH realized motion energy.
The vast majority of places within the US (and times of the year), electricity for vehicles is significantly cheaper (e.g. LA peaks at 16 cents per kWH in the worst conditions according to their power company's website, which is just barely - 20 cents per realized kWH - more than $2 gasoline).
However, we should not expect this analysis to hold if we switched everyone to plug-in power. If we added the energy burden being met by gasoline to the electrical generation system, the cost of gasoline would rapidly decline and the cost of electricity would rapidly rise. Additionally, our infrastructure would have to be upgraded at significant capital cost. The continuous improvement of fuel efficiency in combustion engine vehicles (we didn't even touch on diesel here - 36 kWH per gallon of which 15 can be realized as motion) also detracts from the future projected benefits of a switch to electric.
Therefore, if you are the guy plugging in today, you are probably getting ahead. If we all did it, that would not work. However, a market-based smooth transition one way or the other, or with a continued mix, will probably work out nearly optimally.
As for your question:
Most hybrids do not use plug-in energy, so the fuel mileage is directly comparable. For those that do - remember that plug-in energy is generated from the cheapest stationary source available, is generated in great bulk, and for the most part can be generated from an optimized system (meeting peak demand in the face of all the AC units in LA kicking on simultaneously excepted). We should probably expect that electric is cheaper even though it has to be converted and transmitted.
The cost of electricity generally runs 8 to 25 cents per kWH (you can find even cheaper examples than 8 cents). By contrast, a gallon of gasoline has about 34 kWH of fuel energy which a great car will realize about 10.5 kWH of actual motion energy from. From the plug to the wheel, 80% realization of electricity to motion is not a bad estimate - upstream inefficiencies in electrical generation are accounted for in the kWH price.
The true cost of gasoline is about the pump minus 55 cents or so in most states (including federal and state fuel taxes). You can also figure from the barrel price with a markup for refining and distribution. At today's prices, that puts a gallon of gas at, very roughly, $2 of real cost, or 19 cents per kWH realized motion energy. Electricity by the above estimates comes out to a range of about 10 cents to 31 cents per kWH realized motion energy.
The vast majority of places within the US (and times of the year), electricity for vehicles is significantly cheaper (e.g. LA peaks at 16 cents per kWH in the worst conditions according to their power company's website, which is just barely - 20 cents per realized kWH - more than $2 gasoline).
However, we should not expect this analysis to hold if we switched everyone to plug-in power. If we added the energy burden being met by gasoline to the electrical generation system, the cost of gasoline would rapidly decline and the cost of electricity would rapidly rise. Additionally, our infrastructure would have to be upgraded at significant capital cost. The continuous improvement of fuel efficiency in combustion engine vehicles (we didn't even touch on diesel here - 36 kWH per gallon of which 15 can be realized as motion) also detracts from the future projected benefits of a switch to electric.
Therefore, if you are the guy plugging in today, you are probably getting ahead. If we all did it, that would not work. However, a market-based smooth transition one way or the other, or with a continued mix, will probably work out nearly optimally.
JWaterstreet
Electrical
The greens in California that push electric cars seem to forget that it was less than 10 years ago that California suffered a (admittedly self inflicted) shortage of electricity that led to rolling blackouts across the state.
What would happen if electric cars became popular?
What would happen if electric cars became popular?
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