New Energy Economy

05.29.14

Renewables Can Make Fossil Fuel More Efficient

It takes energy to make energy, and solar or wind power can make recovering fossil fuels less harmful to the environment.
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Renewable energy technologies like solar and wind may seem to be polar opposites of fossil fuel technologies like oil and natural gas. And they are frequently arrayed against one another. Advocates often describe a zero-sum game, in which more of one inevitably means less of the other.

But what if these two powerful forces could work in tandem? What if a wind turbine could help make an oil rig work more efficiently? Or if solar panels could provide the juice that pushes petroleum trapped deep into the earth up to the surface? It takes energy to produce energy, after all. And if some of the energy used in industrial processes can be derived from emissions-free sources, it reduces the environmental impact significantly.

To raise oil from the depths, rigs often inject water at high-pressure into the wells. Typically, the power used to propel the water is derived from steam heat, which is turn generated by burning natural gas.

But innovators believe there are other ways to achieve this goal.

DNV GL, a Norwegian environmental technology company, is working on a way to introduce wind power into off-shore oil production. The idea? Set up a wind turbine that floats on the ocean’s surface, and then use the power it generates to inject seawater into the oil wells. In a press release, Johan Sandberg, a company executive, calls the approach a “WIN WIN—WINd powered Water Injection.” Just as combining peanut butter and chocolate to make Reese’s, which provided a boon to both peanut growers and chocolate manufacturers, Sandberg believes  “the combination of the two technologies can open up an era of synergies and mutual benefit for both industries.” as Sandberg put it. 

A successful version of this marriage is already up and running on land—except it uses solar power instead of wind power.

With the price of oil high, companies are seeking to get the most out of established fields. That’s led to the widespread development of Enhanced Oil Recovery (EOR). Injecting steam into oil fields is the best way of making long-functioning oil wells more productive.

Generally, natural gas was burned adjacent to oil rigs to generate steam. But a few years ago, a California-based company, GlasssPoint Solar developed a way to use sunlight to generate the steam. An array of mirrors enclosed in glass—the better to protect the mirrors from the sand and dirt surrounding oil rigs—reflects sunlight onto a tube containing water. When the tube heats up, it creates steam that can be injected into the oil well. (Here’s how it works.) In sunny regions, the company reckoned, solar energy could account for about 80 percent of the energy needed for oil recovery. 

In February 2011, Glasspoint’s first system was deployed at a small oil field in McKittrick California that had been producing oil since World War I, owned by Berry Petroleum.

Next, GlassPoint took its technology to the desert. In 2012, it built a larger, 7-megawatt system for Petroleum Development Oman’s Amal West oilfield, located in the desert south of the Persian Gulf nation. Each day, the installation of glass-enclosed mirrors—which is more than 25 times the size of the first projectd in California—produces about 50 tons of emissions-free steam. 

Other companies are getting into the act. In Coalinga, California, about 200 miles northwest of Los Angeles, solar company BrightSource Energy and Chevron have teamed up on a slightly different approach. BrightSource has erected 7,644 mirrors in a circle surrounding a 327-foot tower filled with water. Sunlight reflected from the mirrors heats the water and produces steam.

in effect, these efforts are harnessing a highly efficient means of energy production to create greater efficiencies in the production of oil. The U.S. Department of Energy notes that in the first stages an oil well’s life, only about 40 percent of the total oil is recovered. Enhanced oil recovery efforts “offer prospects for ultimately producing 30 to 60 percent, or more of the reservoir’s original oil in place.” And with oil near $100 a barrel, every drop counts.