Pattie Steib/istockphoto
DCL
I'm sure you've heard someone say that the US uses x amount of coal, or natural gas, or wind power. Or that the average us electrical usage per month is, say, 1000 kWh. Or perhaps that the average per capita carbon emissions in the US are about 20 tonnes per year. Which is all fine and good, but that really over-simplifies the situation.
In reality, there are great variations by state, region and level of urbanization in all of these, and they are all closely linked together: In New York a person's carbon footprint is far lower than someone living in Illinois; which is lower than someone living in, say, Louisiana.
Why is this? At the personal level, it comes down to two primary factors: Electricity usage and how that electricity is generated. At the state level it often comes down to the about of heavy industry. Let's look at the numbers for several states:
New York = 53% of National Average
In New York state the Department of Energy reports that the average monthly electricity usage for residential customers is about 590 kWh/month (in New York City it's about two-thirds of that by the way...downsizing your living area has a big impact).
The main source of electricity in the state is natural gas (36%), with nuclear coming in second (29%) and hydropower coming in third (17%). That means that the average carbon emissions from electricity usage in the state comes out to be about 3.25 tons per year.
Combined with other energy usage in the state from industry agriculture and commercial uses, plus the distances people regularly travel, means that per capita carbon emissions for New York state are about 10.75 tons/year. Half the national average.
Illinois = 93% of National Average
By contrast, in Illinois the per capita carbon emissions are pretty close to the national average, at slightly under 19 tons per year.
When you look at electricity usage, you find that the average monthly residential usage is 770 kWh/month. And that the electricity comes nearly evenly from nuclear power (49%) and coal (48%). Which means that from electricity, Illinois residents emit about 5.45 tons of CO2 per year.
Louisiana = 210% the National Average
Then there are states like Louisiana, that by virtue of the type of industry there (lots of petro-chemical manufacturing and refining) plus high electrical usage means that per capita carbon emissions are through the roof. This is skewed somewhat, in terms of how much of an impact that the way people individually live have versus industry, but the per capita carbon emissions there top 43 tons per year.
That said, residential electricity usage is also really high, at about 1260 kWh/month; and when you figure in that 46% of electricity comes from natural gas, 27% from coal, and 19% from nuclear (the remainder is biomass, and other sources), you come on with about 9.3 tons of CO2 emitted per year per person?nearly three times that of New York, and about 1.7 times that of Illinois.
Some Places Are Genuinely More Green Than Others
The goal of all this isn't really to point fingers. Rather it's to illustrate the real impact that the amount of electricity we all use in our daily lives varies greatly across the country, as does the way it's generated.
The regional variations in energy consumption are so widely divergent that any statement that tries to make a claim about what the US does as a whole is only useful at the most broad level. When you look at individual regions you start to see that some places really do things differently and can act as models to emulate.
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