The Department of Energy is promoting development and use of alternative fuels and powertrain technologies.
For a third consecutive week, the average weekly on-highway diesel price increased to a two-year high.
The national average price fell 0.9-cent to $3.162, after falling 1.3 cents the previous week.
The national average price of $3.184 is the highest price since $3.288 the week of Oct. 27, 2008.
The national average price of $3.111 is the highest price in six months. The week of May 10, the price was $3.127.
After three weeks of increases, the average weekly retail on-highway diesel price dropped this week.
For the third consecutive week, the average weekly retail on-highway diesel price increased, rising 0.7-cent to $3.073 a gallon.
DOE raised its diesel-price forecast for the rest of this year by 3 cents to $2.96 a gallon, and for 2011 by 4 cents to $3.14.
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