More than two dozen other states have targets, mostly impossible to compare because their percentages and target years are so different.
New Jersey, for example, has set a goal of reducing emissions to 1990 levels by 2020.
The advisory committee that devised the plan came up with 52 recommendations spanning virtually every sector of the state - its power plants, homes and offices, transportation network, land use, industry, waste handling, farms, and forests.
The most significant reductions, according to the plan, would come from energy generation plus homes and commercial buildings. Millions of tons of emissions could be saved by making buildings - and their lighting systems - more energy-efficient.
Like many states, Pennsylvania could institute "pay as you drive" insurance, giving lower rates to people who drive less. Another recommendation is to reduce speed limits to 55 miles per hour on major highways.
But the plan is merely a draft, and its measures are recommendations that would require legislative or executive action. The public has 30 days to comment.
"The real work will begin after the final plan is issued," said Nathan Willcox, energy and clean-air advocate with PennEnvironment.
The report, mandated by 2008 legislation, was developed by a 21-member committee that includes representatives of government; environmental groups; and the energy, solar, coal, mining, and steel industries.
Jan Jarrett, president of the nonprofit advocacy group PennFuture and a committee member, said some battles were hard-fought. The report lists voting results on each measure, and where dissent occurred the usual lineup was environmentalists and government (13) vs. industry (8).
