The Water That Fuels California’s Power Grid

How many gallons to run that microwave?

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.

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Green Light for Feed-in Tariff to Spark L.A. Renewable Energy

City Council OK’s demo program to buy power from small-scale renewable generators

Feed-in tariffs from private solar arrays like this one enable the world's largest source of renewable energy.

The Los Angeles Department of Water and Power (LADWP) now gets to ramp up a pilot phase that could add up to 150 megawatts of renewable electricity after 2016 — enough to power 22,000 homes — all with an eye toward hitting the state-mandated goal of 33% of its power from renewables by 2020. The measure awaits the mayor’s signature, expected late next week.

A common example of the new program would be a commercial real estate or large warehouse owner installing a rooftop solar power system and selling that power back to the local utility. The simplest definition I’ve found comes from another city that just approved a similar program for solar energy, Palo Alto: “Feed-in tariff programs involve a utility paying a fixed price, a “tariff,” for the power that is “fed into” their electric grid from local generation systems.” Continue reading

California’s Dirty Secret: The Five Coal Plants Supplying Our Electricity

The “invisible” fossil fuel that may be powering your lifestyle

The Navajo Generating Station is coal-fired power plant in Arizona, just outside the Grand Canyon National Park. It's one of two coal plants that supplies more than 40% of Los Angeles' power.

Here in California, you hear a lot about our “green” reputation.  We have one of the most ambitious greenhouse gas reduction goals in the country, and the state is certainly a hotbed for new solar and wind energy investments and installations. We also have a law that says electricity providers have to get 33% of their power from renewable sources by 2020.

So… you might be surprised to hear that coal — that’s right, dirty ol’ coal — is still very much a part of the power supply in parts of Southern California. If you’re one of the 1.4 million residents of Los Angeles who gets power from the city’s Department of Water and Power, about 40% of your electricity comes from coal.

But how’s that possible?  Here in California, we don’t have much in the way of coal deposits, and no significant coal power plants. But we do have several public utilities that own portions of out-of-state coal power plants, and that entitles them to lots of less-than-clean, coal-fired energy. Continue reading

Two-Year Drop in California Carbon Emissions

PG&E substation near San Jose. The drop in emissions applied to both power generated in California and imported from neighboring states. (Photo: Craig Miller)

If you’re ready for some good news on the climate front: California’s carbon emissions from power generation dropped in 2009 and 2010.

That’s according to a new analysis from Thomson Reuters’ Point Carbon that looked at power generated here in California, as well as electricity imported from out of state.

According to the report (available by subscription only), emissions were down 12% over the study period. Part of the drop, not surprisingly, was due the global recession and the state’s slowed economy in 2009. But the study found that even when the economy started growing again, emissions continued to decline.

Sound mysterious? Not really, according to study co-author Ashley Lawson. Continue reading

Report: Solar Panels Boost Home Prices

Photo: Shuka Kalantari

A new study from Lawrence Berkeley National Lab could help California’s homeowners decide whether or not to “go solar.” Researchers found that on average, homeowners who recently installed solar photovoltaic (PV) panels recouped most or all of their investment when they sold their homes.

“A house that has a PV system compared to a house that doesn’t have a PV system is expected to sell for more,” said Ben Hoen, the lead researcher on the study and a principal research associate at Berkeley Lab. “This is for systems that are relatively new – between 1.5 to 2.5 years old.”
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Goldman Prize Winners Reflect Energy, Water Concerns

2011 Prize winner Ursula Sladek (Photo: Goldman Environmental Prize)

The 2011 Goldman Environmental Prize winners were honored in San Francisco last night. In a ceremony at the Opera House, they were each awarded $150,000 for their grassroots work addressing pressing environmental issues around the world.

Environmental degradation from energy production is a common theme in the work of at least half the winners: Dmitry Lisitsyn, who’s worked to protect the ecosystems of Sakhalin Island from rapid destruction caused by companies exploiting the region’s petroleum reserves; Hilton Kelley, for environmental justice work on the Texas Gulf Coast, a region plagued with air-quality-related health problems due to emissions from the major refineries and petrochemical plants in the area; and Ursula Sladek, who created Germany’s first cooperatively-owned renewable power company. Continue reading

Creating Power from Both Light and Heat

A key component of new solar panel technology being tested at Stanford. (Photo: Nick Melosh)

In a kind of cruel paradox, heat has always been the enemy of solar panels.  At higher temperatures, photovoltaic cells become less efficient, which is problematic in an industry where efficiency is the name of the game. That heat also represents wasted energy.

Today, researchers at Stanford University announced that they may have helped solve that problem. Nick Melosh of Stanford’s Materials Science & Engineering department set out to make use of the wasted heat. He and his colleagues created a solar cell technology that uses both light and heat to generate electricity. It’s called “photon-enhanced thermionic emission” (or PETE for short). “This is the first time that a process has been reported that can use the heat and the photons together harmoniously,” says Melosh. Continue reading

The Next Frontier: Artificial Photosynthesis

The ultimate model for clean fuels? (Photo: KQED QUEST)

Amidst all the fretting over the development of solar and wind technology, it hasn’t been lost on some scientists that there are organisms on the planet that have already cracked the renewable energy code: plants.

Photosynthesis is a highly efficient way of converting sunlight to fuel. So why not try to copy them?

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The Solar Jobs Solution: Some Perspective

As anyone who got stuck in the traffic knows, President Obama made a call at one of the Bay Area’s new darlings of green tech, Fremont-based Solyndra Inc., which he called a “testament to American ingenuity and dynamism.”

The firm is tapping more than a half-billion dollars in federal loan guarantees to build a manufacturing plant for its photovoltaic (PV) technology. Governor Schwarzenegger and Energy Secretary Steven Chu have also used Solyndra as a backdrop for showcasing California’s burgeoning clean tech sector. The company has developed a new type of PV technology designed for commercial rooftops.

Solyndra's rooftop solar panels use a new type of cylindrical module. Image: Solyndra, Inc.

Solyndra's rooftop solar panels use a new type of cylindrical module. Image: Solyndra, Inc.

Today in Silicon Valley, the big, green hype machine was running at full tilt. Solyndra’s CEO, Chris Gronet, talked up the California location. “If our factory was someplace else (outside the US), we probably would not have the supply chain across 29 US states,” he told KQED’s Cy Musiker today.

Mike Mielke of Silicon Valley Leadership Group added to the frenzy: “Clearly California’s leadership in the emerging trillion-dollar clean energy technology market has put us in an ideal investment position,” he said in a statement issued after the Presidential appearance.  “We would not be as competitive without the state’s landmark clean energy policies like AB 32.”

But some temperance was injected into the festivities by Severin Borenstein, co-director of the Energy Institute at UC Berkeley’s Haas School of Business. Asked if investments in solar panel production necessarily translate to permanent job growth, he told Musiker: “The evidence from a longer-run perspective really doesn’t support that.”

Borenstein says what history does demonstrate is that dominance in a given technology lasts just about as long as the government subsidies supporting it. He pointed to both Germany and Spain, both of which have recently lost some of their edge in production of solar components. Much production of solar and wind energy products has already moved to China.

“This idea that you’re going to create a permanent competitive advantage in producing green technology by subsidizing it now is really not very well born out in the data,” said Borenstein, who doesn’t deny that federal stimulus funding has “helped push forward” some key technologies. In the absence of a meaningful price mechanism for carbon emissions, Borenstein says that “pushing forward on some of these alternative technologies is the best thing we can do.”

Regarding California’s landmark climate law, the aforementioned AB 32, Borenstein agrees with the state’s Legislative Analyst that implementation would not have a significant impact on California’s overall economy, in either direction. But Borenstein doesn’t see the point in abandoning the state’s primary comprehensive climate strategy to save jobs, as some have suggested it would. “Climate change is real and it is potentially catastrophic,” said Borenstein. “If every time we have an economic setback, we put the environment second, we’re never going to make any progress.”

Capturing Carbon in California

CoalPlantLauren Sommer’s two-part radio series on carbon capture in California airs this week on The California Report. You can also view her slide show at the end of this post.

The idea seems simple enough: In order to get energy, we burn carbon. In most cases, that carbon comes out of the ground in the form of natural gas or coal. So instead of releasing the resulting carbon dioxide emissions into the atmosphere, why not put it back into the ground?

Of course, carbon capture and storage/sequestration (CCS) is much more complicated than that. Nonetheless it’s a strategy that’s being pursued aggressively by both international leaders and US Energy Secretary Steven Chu, who would like to see it deployed in ten years.

There are obstacles on both the “capture” and “storage” side of the equation. In terms of technology, however, “storage” is much further along, thanks to the oil and gas industry, which is already using CO2 in oil recovery. Injecting compressed CO2 into oil fields forces more oil to the surface in a process known as enhanced oil recovery. As many in the industry will remind you, they have three decades of experience doing this.

Keeping it underground is another matter. In the western US, the West Coast Regional Carbon Sequestration Partnership (WestCarb) is setting up a number of pilot projects to study how CO2 can be safely stored underground. As Technical Director Larry Myer explained to me, one of the primary goals is to simply work out the regulatory, siting, and liability issues.

As with any waste issue, choosing the site is the most important–and often most difficult–issue. California’s Central Valley has plenty of underground saline aquifers and depleted oil and gas fields that could hold CO2. But the trick is finding a site where the geology can securely store it and where there’s little risk of groundwater contamination. On the plus side, scientists know that CO2 is slowly immobilized underground, which lessens the risk over time. But how long that takes is still under study.

As for the “capture” issue, there are three ways to separate CO2 from power plant emissions.

  • In today’s Climate Watch story, I describe Oxyfuel technology, in which natural gas is burned in pure oxygen. Since the outputs are steam and carbon dioxide, the CO2 can be easily siphoned off. But that requires building new power plants from scratch.
  • The second option seeks to deal with the carbon dioxide before the fuel is burned; a “pre-combustion” approach. Or for all you wonks out there: Integrated Gasification Combined Cycle (IGCC). The downside to this process is that it requires gobs of energy, which makes it expensive.
  • Finally, there’s the “post-combustion” approach. That’s where the CO2 is “scrubbed” from flue gas after the fuel is burned. Existing plants can be retrofitted with this technology, but it also comes with large energy penalty, just like IGCC.

A price on carbon, through either a cap-and-trade system or carbon tax, would change the economic case for CCS, but there are a lot of strikes against the technology. So why pursue it?

The argument goes like this: In order to achieve steep emissions cuts–say an 80% reduction worldwide by 2050–it may be an important tool (or stabilization wedge).  The world will continue to use fossil fuels in the near term and despite the enormous growth of renewable energy, it’s still a drop in the bucket. That’s why many believe that CCS is a crutch the world needs to wean ourselves from fossil fuels.