'Solar trees' sprout up in California county's parking lots

Aug 28, 2011 By Tracey Kaplan

The frustrating search for a shady spot to park is about to get easier. But the new trees being planted at nine big parking lots in the San Jose, Calif., area aren't leafy green saplings, they're big silver specimens with 12-foot-tall trunks and broad steel canopies that will shield cars from the sun - and produce solar power.

Known as "solar trees" because they are topped with , the "groves" are sprouting up in California at Santa Clara County government buildings and health clinics in San Jose and Gilroy, and at a jail in Milpitas.

The shade they create for cars is just a popular side benefit, though cutting off the sun's glare also will save some energy by reducing the need for motorists to turn on the air conditioning right away in hot weather. The primary benefit of the parking lot projects is that the power they produce will save the county about $18 million in electrical costs over a 25-year period and reduce .

"Most people think it's covered parking, and like it," said Lin Ortega, the county's utilities engineer/program manager.

The majority of solar power in California is still generated by rooftop panels. But parking-lot arrays have been springing up, including at University of California San Diego, where they have been planted on the top floor of two parking garages, and at Google's Mountain View headquarters.

One leading firm, Envision Solar of San Diego, which invented the first solar tree, also makes sun-tracking "trees" that tilt to capture solar rays over the course of the day, producing about 18-25 percent more power, CEO Desmond Wheatley said. The county's first solar trees, installed on the top level of two parking garages at Santa Clara Valley Medical Center two years ago, do track the sun. But they are more expensive to maintain, so the county went with fixed trees this time.

By March, the county will have installed more than 15,000 solar panels in nine parking lots at eight sites. The estimated $18 million in savings over 25 years is minor - less than $1 million a year in a county that now pays $18 million a year for energy. But county officials point to the environmental benefits, saying the projects will reduce carbon dioxide by 4,116 metric tons - the equivalent of taking 800 cars a year off the road. The projects also create at least 92 temporary jobs, they said.

The county is paying for the four smallest projects through a solar-power purchasing agreement with several cities known as a PPA. Under that arrangement, private firms build and own the solar arrays; the county and other cities buy the power at a discounted rate. However, the estimated savings from the PPA turned out to be negligible - only about $2 million over 20 years. Construction on those will begin in January.

So at the urging of supervisors Dave Cortese and Ken Yeager, the county financed its four largest remaining projects through a combination of government incentive programs, including $7.4 million from the California Solar Initiative Program and interest-rate discounts on bonds subsidized by the American Recovery and Reinvestment Act. The county's share will be about $13 million of the $20 million cost, and it will own the arrays. Construction already has begun on the jail and on a two-lot project at the sheriff's office and nearby County Government Center.

"Ken (Yeager) and I urged them to look for a more fiscally beneficial situation," said Cortese, president of the Santa Clara County Board of Supervisors. "We spend $30 million a year on utilities (including garbage and sewer) so there's plenty of motivation to keep moving in the alternative energy direction."

Green as the parking lot arrays are, there's good news for the many county workers and visitors who haven't given up driving. The solar trees at the eight sites will eat up only six of more than 1,000 parking spaces.

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Who_Wants_to_Know
2.3 / 5 (3) Aug 28, 2011
Great way to utterly waste lots of money that the tax payer's don't have - and foist a large chunk of it off on the rest of the nations tax payers who will NEVER see a single minute of benefit from them.

$20 Million up front cost, to 'save' $18 Million over 25 years. Not to mention maintenance costs. Are they completely unable to do even the most simple math??!!! It sure appears Cortese, pres of county board of sups isn't. Well, he probably IS, and is just unethical enough to figure if the rest of the nation is paying for more than half of it, why not stick it to us?

As to "jobs created," people REALLY need to look up and learn about the "broken window fallacy." Also, they're clearly not considering that running existing energy supplies creates jobs too, which will be lost.

But what the heck, it all SOUNDS great, and we can just justify it with the 'ol CO2 meme, right? /sarc
Squirrel
not rated yet Aug 28, 2011
Ignore the capitals and the slight-of-mouth tone of the Who_Wants_to_Know, there is a problem with the press-release rewritten as news. It claims saving of CO2 without factoring in the CO2 costs of construction and maintenance. These are likely to be substantial (all that steel). The real benefit is cooler cars.
Icester
5 / 5 (2) Aug 28, 2011
Who Wants to Know> Let me point out out one addition to your comment.

That is $18 million "saved" over 25 years. That means it is far, far less than $18 million. Much better (for the taxpayer) to put that $20M in a saving bonds (even at the pathetic rates they are getting now) and pull it out in 25 years.
ZachB
3 / 5 (2) Aug 28, 2011
I'm a big fan of solar power and all, but seriously, it's not even affordable with government money. (and that's a big tub of cash)... Consider the disaster government subsidy made of the nuclear industry, and the need to straighten that out, before endorsing another quagmire.
fdgyr
not rated yet Aug 28, 2011
rhjew@hotmail.com
Vendicar_Decarian
1.8 / 5 (5) Aug 29, 2011
"Great way to utterly waste lots of money that the tax payer's don't have." - Tard wants to know

As you have indicated the cost is essentially neutral, with the purchasing costs roughly equaling the cost savings in the not purchasing the energy they generate.

How effective is dependent upon the future cost of energy and how that is accounted for in the accounting (if at all).

The benefits of course are a reduced amount of CO2 entering into the atmosphere and improved quality of the now shaded parking lot.

So it appears to be a lose, win, win situation with the "win" exceeding the lose.

So apparently a good long term - forward looking - decision.

My only concern is if the total life cycle CO2 burden of the towers - from construction to disposal is being compared to the CO2 being conserved. That could change the second win into a neutral or even a slight loss.

Vendicar_Decarian
1 / 5 (4) Aug 29, 2011
"I'm a big fan of solar power and all, but seriously, it's not even affordable with government money." - TardB

Yes absolutely, because as we all know, government money is worth less than private sector money.

Well done Tard Boy, dats somen exehketive levels thinken yooze done dere.
Vendicar_Decarian
1.6 / 5 (5) Aug 29, 2011
"Much better (for the taxpayer) to put that $20M in a saving bonds (even at the pathetic rates they are getting now) and pull it out in 25 years." - Tard C

Absolutely, if the government purchases some government savings bonds and holds then for 20 years then it will make at least 80 percent return on it's money.

Well thought out there Tard C. You is da finantial genie-yuhs.
Vendicar_Decarian
1.6 / 5 (5) Aug 29, 2011
"The real benefit is cooler cars." - Squirrel

Yes, that is my concern as well. I doubt if the entire CO2 emissions for the life cycle for the devices has been taken into account.

These kinds of pilot projects should be tried nevertheless to evaluate their practicality, as well as providing a mass market for solar cells in order to drive up manufacturing levels, and drive down prices.

yoatmon
3.7 / 5 (3) Aug 29, 2011
OK fellows, you're not completely wrong with your deliberations. However, the costs that occur today will be reduced for "tomorrow and the days following".
PV-technology is expensive; yet. But R&D and subsequent improvements will reduce prices and reach grid parity and less in due time.
Remember those prices of the first digital wristwatches, pocket computers, mobiles and PCs?
Drashya
5 / 5 (2) Aug 29, 2011
I don't understand why people tend to be so ignorant about solar power!!! I mean everything from your car to your mobile phone has to be manufactured releasing much the same amount of CO2 (or may be more). So, if you are so much concerned about the CO2 generation then, first go and dump your cars and phones.!!
dutchman
not rated yet Aug 29, 2011
Any picture(s)????
timcharper
3.7 / 5 (3) Aug 29, 2011
It will create 92 temporary jobs with $18 million? The manufacturing of the "trees" will probably cause more CO2 output than the trees will save over the course of 25 years? It will take 25 years for the project to break even? What the heck California? This is why you fail.
tadchem
not rated yet Aug 29, 2011
Judging from the concept designs available on their website, my guess is that resonant vibrations will commence at a wind speed of 40-45 mph. The aerodynamics properties of these palapas are as pitiful as those of Galloping Gertie. There was evidently no thought at all given to wind tunnel testing or to vortex shedding.
gimpypoet
3 / 5 (2) Aug 29, 2011
When electric cars become more popular, these will be test beds for recharger infrastructure. If installed now, they will pay less now, and will charge money to "park and charge". This most likely was not in the impact study, either.
Who_Wants_to_Know
1 / 5 (1) Aug 29, 2011
Who Wants to Know> Let me point out out one addition to your comment.

That is $18 million "saved" over 25 years. That means it is far, far less than $18 million. Much better (for the taxpayer) to put that $20M in a saving bonds (even at the pathetic rates they are getting now) and pull it out in 25 years.

Yes, thank you Icester. That was my suspicion. I wasn't even thinking about how interest would eat into the $$ value - but was pretty certain that a comparable investment elsewhere with depreciation, compounding etc. would make these 'solar trees' a more dismal financial picture than even the basic math shows.
Who_Wants_to_Know
not rated yet Aug 29, 2011
I'm a big fan of solar power and all, but seriously, it's not even affordable with government money. (and that's a big tub of cash)...

Agree! It's awesome for remote locations where other power isn't available or running lines too expensive - or for some space application. Otherwise, it's a bust, and a very bad bust.
Consider the disaster government subsidy made of the nuclear industry, and the need to straighten that out, before endorsing another quagmire.

Huh? What are you talking about here?
Who_Wants_to_Know
1 / 5 (1) Aug 29, 2011
As you have indicated the cost is essentially neutral, with the purchasing costs roughly equaling the cost savings in the not purchasing the energy they generate.


Aside from your childish name calling, it's past time for you to head back to school. The cost isn't anything close to neutral, which is clear with even a basic understanding of financial issues. As presented, there's a 10% loss. That doesn't include maintence costs over 25 years, and I bet it doesn't include the degradation of solar cells over time. Who knows if it includes costs to connect to the grid. Then the return value is significantly degraded over time because of inflation. No private business would invest in something with such a dismal finacial picture, unless incompetant and destined to fail. Only our government plays with our money as if it grows on trees - and that is because they don't have to earn it.
Who_Wants_to_Know
1 / 5 (1) Aug 29, 2011
Yes absolutely, because as we all know, government money is worth less than private sector money.


Yes, it actually is. Why? Because gov. $$ are taken from the private sector, and the process costs a lot of money - so right there, $100 taken from the private sector is less than $100. Then you have to pay the salaries of the gov. workers involved in the process of obtaining that money, deciding where it will be spent, & then administering it along with oversight costs. Plus some incremental loss for the work that $$ could have been doing when instead it was hung up in gov. processes. So for every dollar that comes out of the gov., more than a dollar had to be taken in from the private sector. Or the gov. had to print more, which makes every dollar across the world worth less.
Who_Wants_to_Know
not rated yet Aug 29, 2011
When electric cars become more popular, these will be test beds for recharger infrastructure. If installed now, they will pay less now, and will charge money to "park and charge". This most likely was not in the impact study, either.

Those issues are all hypothetical, with no way to tell if they'll even occur. It's also easy to imagine all sorts of other scenarios that could happen - but you can't put things like that into impact studies, unless it is known that xyz will actually occur (e.g., xyz is already planned, paid for or required by law to be paid for, and in process).

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