California eyes unusual power source: its gridlocked roads

California eyes unusual power source: its gridlocked roads
This Sept. 9, 2016 photo shows rush hour traffic moving along the Hollywood Freeway in Los Angeles. California's traffic-locked roads are being considered for their potential to serve a new purpose as clear power producers. After several years studying the technology, the California Energy Commission is soliciting companies and universities to create small-scale field tests to investigate whether the waste energy created by vehicles, and passed onto roads when driving, could be captured and turned into electricity. (AP Photo/Richard Vogel)

All those cars on California's famously gridlocked highways could be doing more than just using energy - they could be producing it.

The California Energy Commission is investing $2 million to study whether piezoelectric crystals can be used to produce electricity from the mechanical energy created by vehicles driving on roads.

The commission is in the process of choosing a company or university to take on small-scale field tests. It will study how the small crystals, which generate energy when compressed, could produce electricity for the grid if installed under asphalt.

Scientists already know the technology works, but the state needs to figure out whether it can produce high returns without costing too much. Similar projects in other parts of the world have been discontinued.

"It's not hard to see the opportunity in California," said Mike Gravely, the commission's deputy division chief of energy research and development. "It's an energy that's created but is just currently lost in vibration."

Scientists say it's a matter of shifting perceptions.

"No longer is driving just the act of using energy. Maybe it's also part of the process of generating it," said Paul Bunje, a scientist at a Los Angeles-based nonprofit that funds technological developments and the former founding director of UCLA's Center for Climate Change Solutions.

The hope is that the use of clean energy produced by roads will help the state reach its goal of producing 50 percent of California's electricity with renewables by 2030, Gravely said.

The state is on target to reach 25 percent by the end of the year, according to the .

Whether the technology can withstand the wear and tear of traffic is something that concerns Joe Mahoney, a professor of civil and environmental engineering at the University of Washington in Seattle.

"One would need to consider which would last longer: the pavement or the devices," he said, adding highways need to be resurfaced every 10 to 30 years.

There is also uncertainty about whether the technology will be competitive enough with other renewables to merit full-scale investment.

California's funding to study the technology follows a series of projects in Tokyo, Italy and Israel that appear to have failed or been dropped.

Most notably, an Israeli company whose pilot test attracted global attention in 2009 is now in the process of liquidation, and the project was unsuccessful, according to the Israeli roads authority.

The company, Innowattech, also had plans to install its devices under a section of Italian highway but pulled out, according to Salini Impregilo, the Italian construction company involved.

It was the Israeli project that inspired California lawmaker Mike Gatto, a Los Angeles Democrat, to ask the energy commission to fund pilot projects in California.

Gatto submitted a bill to the Assembly in 2011 and has lauded the Israeli project in several news releases since.

He told The Associated Press that he didn't know the project apparently failed.

"Hearing these details for the first time —obviously, they're not heartening," Gatto said. "I don't want anything to be colored by one tiny experiment by one company in a different country."

Gatto said he thinks the technology is still viable.

"It's probably that there are cost issues that might have been present in Israel that might not be present here," he said.

Innowattech data also featured heavily in the commission's feasibility study, published by an energy consulting company in 2014. The study gathered and compared the data available from projects experimenting with the technology at the time.

But the commission's Gravely said conclusions were drawn from a range of sources, assuring him the results are reliable. He added he has spoken to several manufacturers within the United States who are eager to explore it.

Bunje noted it's not uncommon for a technology's early adopters to fail.

"Innovation comes with risk," he said. "There is a general rule that you don't know what is going to work."

Regardless of the risks, it's worth trying new things, he said.

The $2 million California is using to test the new technology will come from a renewable investment fund created by the California Public Utilities Commission. Bidding will end Nov. 18, and the commission will award the contract in the spring.

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Sep 25, 2016
Solar Freaking Roadways!! Errr, no - if it's gridlock, cars would be covering the solar cells and yeah, traffic would pound those cells to rubble in short order.

Piezoelectric Roadways!! Errr, if the traffic is gridlocked, then there's not much movement to generate power, is there?? Seriously, this feels like it is harvesting energy from the passing cars - that seems like theft unless the loss to the cars would have happened anyway, the piezoelectrics just harvest what would otherwise have been wasted. Seems less ridiculous than solar roadways, so go for it. Try it and let us know if it is practical.

Sep 25, 2016
Why doesn't California harness another resource they have, an abundance of B and C list celebrities? They could act as celebrity coaches at special spin centers where the exercise bikes are fitted with generators. Hundreds or even thousands would show show up and generate electricity while listening to the likes of Kim Kardashian talk about her personal life!

Sep 25, 2016
Piezoelectric Roadways!! Errr, if the traffic is gridlocked, then there's not much movement to generate power, is there??

There is also engine vibration...

Sep 25, 2016
piezoelectric roads have got to generate more tire rolling friction. The energy has got to come from somewhere. This means that the electricity is generated by wasting more gas. Nothing is free.

These promotors are trying to pull a fast one over the public.

Sep 25, 2016
Well it is good to see that someone's brother-in-law is getting a nice grant.

Sep 26, 2016
This is the dumbest thing I've seen yet, it will require cars to burn more gasoline to inefficiently generate some more energy. How is burning fossil fuels inefficiently green? And it's no more renewable than the gasoline that is powering the vehicles.

Sep 26, 2016
Why would it REQUIRE the vehicle to burn more gas? The point is that there is lost energy in the form of vibrations and movement on the pavement. The idea is to harness that waste. I dont have a clue where you people are getting the idea that MORE energy has to be created for this to work.

Seriously, for people who are visiting a science site, it seems like so many of you damn people are naysayers where every new idea is a bad one. I find it mind boggling.

Sep 26, 2016
Seriously, this feels like it is harvesting energy from the passing cars

That's because it is. The harvesting is bought at the cost of having the surface give (the piezocrystals must be compressed and then must decompress to their original state after the car has passed).
Essentially They're building a road made of rubber. That cars don't get the same gas mileage on a rubber road than they do on a concrete one should be fairly obvious. The energy that is harvested isn't 'free'. The cars will give it up (using more gas) and the transmission losses (heating of a 'soft' surface) will even mean that cars will use up *even more* gas in addition than you get out of the system.

Of course the beauty is that drivers pay, while the state gets to sell the electricity. Read: It's a tax.

(Oh, and roads get a lot more expensive and also don't last as long. Variable surfaces have a *bad* longevity record under traffic.)

Sep 26, 2016
Now as for the "solar road" idea: When this came up a couple years back I thought it was a terrible idea. And I still think it is unless this can be incorporate into roads automatically and at next to no cost without adding maintenance or shortening longevity of the road covering. A tall order to say the least.

The dutch trial with a solar bikeway is going "unexpectedly well" (though compared to the cost it is far, far, FAR from economical)
At a cost of 3.7 million dollars it has returned enough energy to earn it just over 2500 dollars in Netherland's electricity prices. I.e. to make this economically viable over a 20 year lifespan the cost has to come down by a factor of 50 - at least.
No longevity data is available, yet (and remember: this is a road for emissionless bikes. Not exhaust producing/heavy trucks and cars)

I don't see this happening in the near future.

Sep 26, 2016
This comment has been removed by a moderator.

Sep 26, 2016
""No longer is driving just the act of using energy. Maybe it's also part of the process of generating it," said Paul Bunje, a scientist at a Los Angeles-based nonprofit that funds technological developments and the former founding director of UCLA's Center for Climate Change Solutions."

It is stupid statements like that which cast a cloud of doubt over all of climate science. The fact that he was a director makes it even worse.

Sep 26, 2016
Ah...Climate Change...the cash cow that just keeps on giving.

Sep 27, 2016
If the in road devices take energy from the road - car interface it can only come from the car's petrol tank. That is theft.

Sep 29, 2016
More airy-fairy stuff from the Calikook libs. How's that $65 billion train coming that no one will use and will cost more than airfare to travel in?

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