Kristen Arnold, Upper Arlington,  Ohio State student: Arnold says wind and solar energy are flourishing in Ohio with an estimated 80,000 related jobs. "How do john McCain and Barack Obama plan to implement green jobs in the rest of the country?"

Politicians always promise to create jobs, and this year's presidential candidates are no exception. Here's another news flash: Politicians tend to exaggerate.

Sens. John McCain and Barack Obama are both touting energy plans that they say will create "green jobs." Millions of them.

The candidates say those new jobs not only will reduce the nation's dependence on foreign oil but help turn around the floundering U.S. economy.

In the second presidential debate earlier this month in Nashville, McCain said, "We can move forward and clean up our climate and develop green technologies and alternate -- alternative energies for -- for hybrid, for hydrogen, for battery-powered cars so that we can clean up our environment and, at the same time, get our economy going by creating millions of jobs."

Obama, at the Democratic National Convention in August, said, "I'll invest $150 billion over the next decade in affordable, renewable sources of energy -- wind power and solar power and the next generation of biofuels; an investment that will lead to new industries and 5 million new jobs that pay well and can't ever be outsourced."

So, Obama says he will create 5 million jobs and McCain promises to create "millions" while cleaning up the environment and combating global warming.

That sounds great amid job losses, foreclosures, gas prices and the mess on Wall Street, but can either candidate deliver?

Experts are skeptical. They say the claims are overly optimistic, given the hurdles both plans will face.

"When they start talking about millions of good-paying jobs, I have my doubts," said Andy Keeler, an environmental economist at the John Glenn School of Public Affairs at Ohio State University.

So, what makes a job green?

Generally speaking, green jobs are those that focus on expanding the use of alternative energies, cleaning up the environment and conservation efforts.

Think construction workers to build energy-efficient buildings, engineers to design nuclear plants, lawyers specializing in environmental issues or electricians to install solar panels.

Obama's pledge to create 5 million new green-collar jobs comes in large part from his plan to inject $15 billion a year into research and development of clean-energy technology.

A "new energy economy can be an engine that drives us into the future the same way the computer was the engine for economic growth over the last couple of decades," Obama said during the second debate.

David J. Bayless, a mechanical engineer and director of Ohio University's Coal Research Center in Athens, agrees with Obama's idea of investing in research and development but cautions that government can't create green jobs on its own.

"It is still going to take private market forces to adopt this," he said.

Bayless noted that government incentives already exist to promote solar power, yet you still don't see many homes with solar panels.

Obama also promises to create new green jobs through energy efficiency, pledging to modernize 1 million homes per year, enacting stricter appliance standards and phasing out incandescent light bulbs.

That's the part of Obama's plan, experts say, that would create jobs quickly, as in workers to weatherize homes, but it is unclear how well-paying the jobs will be.

McCain's promise to create millions of jobs stems mostly from his proposal to build 45 nuclear power plants by 2030, and ultimately 100 nationwide.

"Nuclear power is safe, and it's clean and it creates hundreds of thousands of jobs," McCain said during the second debate.

McCain also pledges to spend $2 billion a year to develop clean-coal technologies that he says also will lead to new jobs. He proposes a permanent tax credit equal to 10 percent of wages spent on research and development.

McCain's plan to build nuclear power plants would cut carbon emissions, but the plants will not be easy to build, experts caution.

The nuclear industry is heavily regulated, plants are extremely expensive to construct, citizens have concerns about safety and there is no plan for what to do with radioactive waste.

"The logistics of getting that many built that fast is overly optimistic," Keeler said. "And getting communities to agree to take them? In Ohio, we can't even build a windmill in Bellefontaine."

ccandisky@dispatch.com