How many gallons to run that microwave?

Lauren Sommer / KQED

A natural gas power plant in Long Beach that uses "once-through" cooling.

We hear a lot about how green our energy is in California. Instead of using coal, the state runs on natural gas and increasingly, renewable power.

But there’s a hidden cost to our energy supply: water use. In fact, every time you turn on a light, it’s like turning on your faucet. It’s been calculated that it takes 1.5 gallons of water to run a 100-watt light bulb for 10 hours.

The way water and power work together is a lot like a tea kettle. Steam drives the power industry.

How Power Needs Water

You can see it at the Gateway Generating Station, a natural gas power plant in the northeast Bay Area. The plant looks complicated but making power is pretty simple. Step number one: burn natural gas. That produces a lot of heat.

“You’ve got 1,700-degree exhaust energy, or waste heat,” says Steve Royall of PG&E, who is giving me a tour through the maze of pipes and compartments. The heat hits pipes that are filled with water and the water is boiled off to create steam. That’s step number two: make steam to turn a steam turbine, which is attached to a generator. It’s the water that’s making the power.

Source: National Renewable Energy Laboratory. Illustration by Andy Warner.

But water has another job in power plants. That steam, even after it makes power, is still hot. So, most power plants use water to cool it down. “You’ve got to have the ability to cool everything down so the cycle can continue and your equipment doesn’t overheat,” says Royall. (Learn more about how power needs water in this illustration).

Nuclear plants and coals plants use water the same way, in some cases, millions of gallons a year. In fact, nationwide, power plants need more freshwater than farms do, according to a U.S. Geological Survey study.

Newer power plants reuse water, but a lot of it is lost to evaporation, which means it has to be replenished. “Typically water has been the most abundant resource available,” says Royall, “but as water resources become more valuable, it’s extremely important that we think about water use.”

Future of Water Scarcity

“There is a general understanding that the era of abundance is over,” agrees Heather Cooley of the Pacific Institute, an Oakland-based think tank focused on water issues.

“Water resources are limited and there is a growing demand. We have growing population in the West. We have a growing economy.”

And then there’s the climate – which is changing. “The climate models suggest that water availability will be more variable. So we’ll have wetter years, we’ll have drier years. We’ll have a smaller snowpack,” says Cooley. In some places, power plants are already feeling the effects of tightening water supplies.

Power plants can cut their water impact by using recycled water. “We can look at less water-intensive renewable energy systems. So looking at wind and at solar panels,” says Cooley.

But it turns out, some renewables need water, too.

Solar Technology Grapples with Water Costs

In a parched corner of California’s Mojave Desert, construction equipment shimmers in the mid-day heat. These 3,500 acres near the Nevada border are the site of the Ivanpah Solar Project.

“The Ivanpah project, when it’s operational, will be the largest solar thermal project operating in the world,” says Joseph Desmond with BrightSource Energy.

You’ll notice he said “solar thermal,” a technology that’s different than the solar panels you see on rooftops. The plant is a huge field of mirrors that are specially angled to focus the sun’s heat at a tower, 400 feet tall.

“Inside the top of that tower is a boiler. All of the energy is then is used to create high temperature, high pressure steam in excess of 1,000 degrees Fahrenheit,” says Desmond.

That spins a steam turbine that makes electricity. Just like a natural gas plant, that steam has to be cooled back down, which is normally done with water. In the desert, it’s not easy to find. “You have to dig down, I want to say about 840 feet,” says Desmond.

The Ivanpah solar project under construction. (Photo: BrightSource Energy)

So, the Ivanpah plant will use a new technology called “dry cooling.” Instead of using water, the plant uses massive fans to blow air over the pipes of hot steam. “Air cooling allows us to reduce the water consumption by as much as 90%,” says Desmond.

But there’s a catch. Dry cooling uses more energy, so the plant’s not as efficient. It’s even less efficient when it’s hot out.

It also costs more to build. “It can range between one and five percent more. Now, that may not seem like a lot but when you’re competing and every penny counts, it’s an important factor,” Desmond says.

Three of the seven solar thermal plants planned in California won’t use dry cooling. But Desmond says, even though the state needs renewable power, he doesn’t think agencies would approve that today. “I think it’s safe to say if somebody said we’d like to use water cooling, that getting a permit for that would be challenging to say the least.”

The same could be true for fossil fuel plants, too, as California’s future water supply is called into question more and more.

Explore the Water and Power series and hear Lauren’s radio story on KQED’s The California Report.

Tesla Motors

Elon Musk is the founder of Tesla Motors and SpaceX, and supported the creation of SolarCity.

Elon Musk is well-known in Silicon Valley as the founder of the luxury electric vehicle company Tesla Motors, and of SpaceX, the private space transport company.

What’s less well-known is Musk’s contribution to SolarCity, the solar installer and energy efficiency auditor. Musk inspired–and helped fund–the creation of the San Mateo-based solar company. And Tesla is working closely with SolarCity on a clean energy storage solution that would combine Tesla’s lithium-ion batteries with SolarCity’s rooftop solar arrays. The collaboration makes sense: not only is Musk the chairman of SolarCity, but the founders of the company, brothers Lyndon and Peter Rive, are his first cousins.

The Tesla-SolarCity clean energy storage program would couple batteries with solar arrays, providing a way to store solar energy for, say, a cloudy day. Stage one of the project began in 2010, with $1.8 million in funding from the California Public Utilities Commission (CPUC) to launch a research program. Now, stage two seeks to commercialize the program on a modest scale, with over 70 applications pending under the CPUC’s  Self-Generation Incentive Program (SGIP), which provides rebates to customers using self-generated energy systems.

Although the subsidies have yet to be approved, CPUC information officer Andrew Kotch told GigaOm last week, “this emerging technology has a great amount of potential to contribute towards California’s climate and energy goals.” At present, the projects have a “conditional reservation,” and the CPUC will make a decision in the next 18 months.

As chairman of SolarCity, Elon Musk is not involved in such details or the day-to-day operations of the solar company, and CEO Lyndon Rive admits that his cousin’s time is very limited. He only contributes “maybe two hours a month” to the company — by phone — and three hours every quarter for board meetings. For your average chairman, that’s not much time to have a significant impact on a company. But Musk appears to have a rare gift for out the box thinking and strategizing.

“Elon is a phenomenal genius, so when he gives you the time and you lay out the plan, he can quickly identify the hole in the plan,” Rive told me. “This is the true definition of quality versus quantity. You can fix whatever potential pothole you might run into, just in a ten minute discussion with Elon.”

Musk manages to juggle all these projects — plus go to Burning Man — as Lyndon Rive explained in a recent Fresh Dialogues interview. In 2004, on a road trip to Burning Man, Peter Rive told Musk he wanted to do something that had a larger environmental impact, and Musk came up with the initial idea for SolarCity.

Was it was the profusion of attendees using free-standing solar panels to power their RVs? The atmosphere of radical creativity? Or was it just witnessing all that carbon going up into the desert air? Whatever fueled the conversation, it has had a profound impact on the US solar installation market. Last year, SolarCity had the largest share of residential solar installations in the US, and thanks to investments from Google and others, it’s growing rapidly, currently hiring four new employees a day. Like his cousin, Lyndon Rive has stratospheric dreams. Rive told me his ambitious goal is world domination in the energy market, no less. An IPO is anticipated later this year.

Courtesy BrightSource Energy

When it

Here’s the fine print up front: this survey, conducted during December and January, was underwritten by BrightSource Energy, the company that’s building one of California’s largest solar projects at Ivanpah, northwest of Needles in the Mojave Desert. Private capital for Ivanpah came from Google and from CalSTRS, the state’s teachers’ retirement system. It’s an enterprise that’s been lauded by Governors Schwarzenegger and Brown, by U.S. Interior Secretary Ken Salazar and President Obama.

But just this week, Ivanpah came under fire in a Los Angeles Times story boldly titled “Sacrificing the Desert to Save the Earth.” BrightSource took to its own website to refute the charge that their utility-scale solar effort is responsible for “razing the desert” and pointed to their “low impact design,” a native plant nursery on site and a “Head Start” program for juvenile desert tortoises.

All that said, the phone survey conducted by Probolsky Research, LLC and released today by Vote Solar, a non-profit advocacy group, shows jobs and the economy leading the list of concerns among 52.3 percent of those polled, horse lengths ahead of a host of other woes which only garnered single-digit responses, including “environmental issues.” Only 5.5 percent put that at the top of the list.

Two noteworthy items from the five counties (Inyo, Kern, San Bernardino, Riverside and Imperial): a robust 56.6 percent said they were “concerned” about “global warming, otherwise known as climate change,” with a healthy minority of 42.2 percent saying they were “unconcerned.” When surveyors asked which kind of energy they’d rather have in their community — they could choose as many as they liked — renewables won the first spot with 60 percent picking “solar fields” and another 46.5 percent choosing windmills. Oil exploration and natural gas “fracking” were a distant third and fourth, with half and a third as many votes respectively.

These answers come as a bit of a surprise because according to the Bakersfield Chamber of Commerce, if Kern County were a state, it would come in fourth in oil production for the nation, just behind Texas and Alaska and the state of California itself. These are not historically the places one would think would embrace alt-energy at the wholehearted rates in this survey.

Finally, more than three-fourths agreed that “parts of the California desert” should go to renewable energy projects, and three-fourths support building large-scale solar generating projects there. Did the survey pose a specific question about environmental concerns with “big solar?” No. But Vote Solar’s Jim Baak is taking a comparative and larger view.

“What we’ve been seeing and hearing is that ‘business-as-usual’ will do far more damage than large-scale solar,” said Jim Baak, one of Vote Solar’s policy directors. “California deserts are fragile ecosystems but the single greatest threat to deserts is climate change.”

Lisa Aliferis / KQED

Rooftop solar panels on a home in Oakland.

San Jose comes in third with more than 2,700 rooftop installations, while San Francisco comes in fourth with more than 2,400 (though it’s fifth in terms of overall capacity). San Diego leads with 4,500-plus installations producing almost 37 megawatts of electricity.

“I think the story with San Diego is that the city was an early and very consistent adopter of solar power,” says Michelle Kinman, clean energy advocate with Environment California Research & Policy Center. “San Diego also has a really well coordinated working relationship between the local elected officials, the utility, the solar industry and the advocacy community.”

Several of the top cities on the list have doubled their solar capacity in just the last two years. In 2000, California had fewer than 1,000 rooftop installations. That’s grown to 100,000 installations in 2011, which makes up more than one gigawatt of distributed energy. “Solar is really taking hold,” says Kinman. “The costs are coming down. We’ve had solar policies at the state and local level for several years and they’re proving themselves.”

Kinman says they’re seeing solar spread throughout the state to the “agricultural and industrial hubs of the Central Valley. Solar power is really taking hold in both rural and urban areas across the state.”

The solar industry has certainly had a boost from rapidly falling prices on solar photovoltaic panels, which dropped a whopping 50% in 2011 alone. Industry analysts say prices could keep falling. According to GTM Research, an oversupply of high purity silicon (a source material for solar panels) could drive down silicon prices this year, which means manufacturers could sell panels for even less.

Rooftop solar has also grown thanks to solar-leasing programs, where consumers realize cost-savings immediately, instead of buying the solar system themselves. Solar leasing has surged in Southern California, according to a recent report from the National Renewable Energy Laboratory. It grew from 9% of residential solar installations during the first quarter of 2009 to 36% during the first quarter of 2011 (among projects tracked by the California Solar Initiative database).

Solar leasing is also more popular with low-income households and in neighborhoods with younger families, according to the report. NREL study author Easan Drury says leasing options have attracted new solar customers in different demographics and has shown to be an even bigger draw than cheaper solar panels.

To maintain the growth in distributed solar, Kinman wants to see a lift on the net-metering cap for California utilities. Right now, utilities are only required to sign contracts with residential solar customers for up to 5% of their overall power load. She also supports a robust feed-in-tariff program. “Feed-in-tariffs have been used the world over and a really one of the most trusted policies for driving a solar market. “

Hear the companion radio feature Wednesday morning, on The California Report.

Sasha Khokha/KQED

Aaron Barcellos and his yellow lab, Maddox. Barcellos hopes to plant rows of pomegranate trees next to rows of solar panels.

Farmer Aaron Barcellos bristles at the idea that putting solar panels on his land is “paving it over,” as some critics have contended. Harvesting electrons, he says, is not the same as pouring concrete to build houses or a shopping center. Solar isn’t permanent: he can simply pull out the posts holding up the panels when he wants to plow the land under again. In the meantime, using a small part of his farm to generate power for the grid is a good way to bring in some guaranteed income, helping him weather the ups and downs of drought and crop prices.

But on Barcellos’s farm, the ground closest to a PG&E substation is considered “prime” farmland. That means he has to get permission from county supervisors to take his land out of the Williamson Act, which gives farmers a tax break for keeping prime farmland in agriculture. I explore that controversy in my radio story on today’s California Report.

A new joint report from UC Berkeley and UCLA (a big pdf) estimates that California could need 100,000 acres of land to meet its renewable energy targets by 2030. But it warns that the state needs to define which land is optimal for solar development, or else it risks losing prime farmland.

Sasha Khokha/KQED

A new kind of harvest: workers install more than 16 thousand posts that will hold up solar panels on this PG&E-owned solar farm in Western Fresno County. This field used to grow tomatoes.

That’s exactly the fear of the California Farm Bureau. It’s suing Fresno County over its decision to allow a solar development on land protected by the Williamson Act. The fight places the Farm Bureau, usually a fierce defender of property rights, in the odd position of squaring off against willing property owners over what they should be able to do with their land.

Fresno County Farm Bureau President Ryan Jacobson says the sheer magnitude of the 30-or-so projects proposed for Fresno County is a threat to the nation’s most productive farm county. (Check out a recent map of proposed solar projects in the county.)

“The reason Fresno County is the number-one agricultural county in the world is because of our large tracts of uninterrupted land,” says Jacobsen.  “We’re concerned about these industrial uses breaking that up. [Farming] is one of the very few bright spots in our economy right now and unfortunately, we’re paving it over.”

Jacobsen also warns solar panels don’t necessarily make good neighbors in farm country. Bees that pollinate orchards can gum up the surface with sticky pollen. Layers of dust from neighboring farms can settle on panels, reducing their output.

But Barcellos says he’s not concerned.  “We’re fourth generation farmers,” he says. “If I thought this was something that wasn’t compatible with farming, my family just wouldn’t be interested in it.”

Courtesy of SolarGen USA

Barcellos wants to see if the shade from solar panels can actually benefit crops like pomegranates.

In fact, he’s one of the first farmers planning to experiment with planting crops next to solar panels – using the shade to protect his delicate pomegranates from sunburn. “The plan is to have two rows of pomegranate trees between two rows of panels. They’d get sunlight 55 percent of the time, and be shaded the rest of the day,” explains Barcellos. It’s an experiment researchers at San Diego State plan to follow closely, to see if it can be duplicated elsewhere.

Farmland conservation advocates say they’re not against renewable energy. Their ideal solution would be to put solar on less productive farmland. But that doesn’t always work logistically, especially if that land is far from transmission lines. The UCLA/UC Berkeley study recommends upgrading electricity infrastructure to make it easier for more remote, less productive fields to connect to the grid.

CORRECTION: An earlier version of this post identified Aaron Barcellos as “Tom Barcellos.” We apologize for the confusion — especially to Tom Barcellos, who alerted us to the discrepancy.

Craig Miller/Climate Watch

The 1603 program reimburses companies for a portion of the cost of installing solar projects.

Solar companies benefit from a 30 percent tax credit, but there’s a problem: most companies developing solar projects don’t have enough income to take the deduction. That’s where the 1603 treasury grant program comes in. It gives companies a cash grant up front in place of the tax credit.

“This program really was a fix that brought liquidity back to the market and enabled developers to move forward with their projects,” said Arno Harris, the CEO of Recurrent Energy, a San Francisco-based solar developer. “It’s definitely going to have an impact, if it’s not extended, on our appetite to continue investing in the US solar market.”

According to Harris, most solar companies depend on the tax program. But he says there is some good news (at least for his company). Solar is looking more attractive to investors, including Google, for one, which recently announced it’s investing $94 million in four of Recurrent’s solar projects.

Hear Lauren Sommer’s radio story on KQED News.

A gigawatt – or a thousand megawatts – is enough energy for about 600,000 homes. Only five nations — let alone states — including Germany and Japan, have reached that level. “Even in a bad economy, the solar industry has been growing exponentially by 40 percent per year,” says Michelle Kinman of Environment California.

The goal comes five years after California’s Million Solar Roofs Initiative began, which mandates three gigawatts of rooftop solar by 2016.

The report credits the rapidly falling prices of solar panels for the growth, as well as the California Solar Initiative, a $2 billion solar rebate program. In 2007, the program provided a rebate of up to $2.50 per watt. As demand has grown, the program is designed to reduce the incentive. Today, it’s between 25-65 cents per watt.

“The real goal of the program is to create a sustainable solar industry in California that will continue to thrive without continued ratepayer incentives,” Scott Murtishaw of the Public Utilities Commission. “And I think that we’re achieving that. The installed cost of solar has fallen by roughly a quarter since the program began.”

The report says California is on track to meet the three-gigawatt goal in 2016. Adam Browning of Vote Solar says the state’s net metering cap could get in the way. Solar customers sign up for net metering contracts with their utility, so they’re credited for the electricity they generate. Right now, California utilities are only required to sign contracts for up to 5% of their overall load.
“There are clouds on the horizon and we’re going to have to lift the cap again,” says Browning.

Still, he says it’s a good story. “We’ve hit that transformation point with solar. It’s like cell phones. They’re nowhere until they’re everywhere. Once they hit a sweet spot, you see an explosion and I think that’s what’s happening now.”

Gretchen Weber

Construction of one of three planned solar thermal towers at the Ivanpah Solar Electric Generating System, Ivanpah Dry Lake, CA

Construction of the Ivanpah site is reportedly on-schedule for completion in 2013

The National Clean Energy Summit 4.0 opens in Las Vegas on Tuesday, bringing policy makers and industry leaders from around the country together to “chart the course for the future of energy in America.” It’s also attracting lots of media, which is why on Monday Oakland-based BrightSource Energy opened the gates to the construction site of its 3,500 acre Ivanpah Solar Complex, which lies just over the California border, 45 minutes southwest of the Las Vegas Strip.

About 15 reporters donned hard hats and safety goggles in 100-plus temperatures to tour the active construction site in the Mojave Desert, along with officials from BrightSource, San Francisco-based construction company Bechtel Corp., and NRG Energy, which, along with Google, is the project’s main investor.

Touted as the the largest solar thermal plant under construction in the world today, the 370-megawatt array is expected to power 140,000 homes when it’s completed in 2013.  BrightSource officials say that will double the total solar thermal capacity of the entire United States, and increase the world’s supply by about a third.

Gretchen Weber

Ivanpah constuction from a distance

The site will eventually consist of three towers more than 450-feet tall and 53,000 “heliostats” dotting the surrounding acreage. Heliostats are the mirrors that focus the sun’s energy onto a boiler at the top of the tower, creating the heat necessary to generate steam and energy.

BrightSource’s Carlos Aguilar said that by employing a technology called dry cooling, which uses air to cool the plant instead of water, the site will use 97% less water than it otherwise would have. The project is slated to use about 100 acre-feet of water per year, which, he said, is about the amount used by 300 homes in a year.

“Three-hundred homes’ worth of water use for 140,000 homes’ worth of energy is quite a trade-off,” said Aguilar.

Another low-impact environmental strategy at the site includes efforts to keep the natural contours of the land intact, in order to keep the natural drainage system functioning.  And according to BrightSource CEO John Woolard, because the plant is 50% more efficient than a photovoltaic installation, it’s able to encompass a smaller footprint.

“We’ve got probably the lowest environmental impact of any technology out there in solar,” said Woolard.

Gretchen Weber

That hasn’t stopped activists from organizing pickets outside the company’s headquarters in downtown Oakland. Ivanpah has been the target of some environmental groups arguing that the solar installation threatens the endangered desert tortoise.  In April, the Bureau of Land Management shut down construction on two sections of site when more tortoises were found on-site than expected. But in June, after further environmental review, the agency granted permission for work to resume. On Monday, Bechtel and BrightSource officials said the project is on schedule.

The event was an unusually high-profile affair for BrightSource of late, as the company is preparing for an initial public offering of stock and is in an SEC-enforced “quiet” period.

Craig Miller

California’s three big utilities have another two years to reach their mandated target of having 20% of their electricity generated from renewable sources, and today PG&E announced two new deals that could inch the company closer to that goal:

• Wind:  An agreement with NextEra Energy Resources, for 25 years of wind power from the company’s 163 megawatt North Sky River project in Tehachapi, CA.  PG&E says the energy from this project could meet the needs of about 90,000 typical homes.

• Solar:  A 25-year contract with Sempra Generation for 150 megawatts of solar power from an expansion of the Copper Mountain Solar complex near Boulder City, NV.  Just under 2/3 of that power is expected online in 2013, with the remainder available by 2015. Ultimately, the company says, this project could power 45,000 homes.

PG&E spokesperson Lynsey Paulo said that together, these two contracts will push PG&E one percent closer to the 20% goal.

As of last week, PG&E was at 15.9% of electricity generated from renewables, according to latest numbers out from the California Public Utilities Commission (CPUC).  Southern California Edison is a 19.3%, and San Diego Gas & Electric is at 11.9%.

The official Renewable Portfiolio Standard (RPS) is 20% by 2010, but the CPUC has implemented flexibility allowing the utilities until 2013 to meet the requirement.   Ultimately, the legally-mandated RPS requirement is 33% by 2020.

For more on California’s quest for renewable energy, check out our multimedia series 33×20: California’s Clean Power Countdown.

Craig Miller

Governor Brown moves forward with plans to encourage more local solar generation in the state.

California has been on something of a solar frenzy recently, approving permits for more than 4,000 megawatts of new solar power in 2010 alone. Most of that is in the form of large, industrial-scale installations, which will provide lots of power, but also will require transmission infrastructure to get the clean energy from the desert sun to where its needed, primarily, the coastal cities.

This week Governor Jerry Brown is focusing on the other kind of renewable energy: the local kind that is smaller in scale and doesn’t require transmission to get where it’s needed. He’s hosting a conference at UCLA this week to promote his eight-point energy plan announced in June, and map out how the state can meet his goal of 12,000 megawatts of local, renewable energy by 2020. That goal would basically quadruple the state’s current supply of small-scale renewables, according to the non-profit Environment California. The Brown plan consists of specific goals but leaves creation of incentives to regulatory agencies such as the California Energy Commission.

In 2006, former Governor Arnold Schwarzenegger signed the Million Solar Roofs Initiative, which aims to build 3,000 megawatts of rooftop solar power by 2016.  As part of this program, the California Solar Initiative provides incentives for installations on homes and commercial buildings for customers of the state’s state’s three investor-owned utilities: Pacific Gas and Electric Company (PG&E), Southern California Edison (SCE) and San Diego Gas and Electric (SDG&E).  Currently, total small-scale installed capacity in California is 924 megawatts, including 194 megawatts that were installed in 2010, according to the California Public Utilities Commission.