Gigawatt scale solar thermal generates steam for enhanced oil recovery

Using solar thermal technology to grab more oil from the earth is now a major opportunity, to the tune of $114 billion, according to the head of Glasspoint Solar.

Solar thermal-enhanced oil recovery is a technique where steam produced from the heat of the sun is injected into an oil reservoir, facilitating the crude’s flow to the surface. Thermal recovery processes have traditionally burnt natural gas to produce steam. The use of alternate methods is driven by the need to send natural gas resources to the local power market or for export.

Solar thermal technology is already at work in concentrated solar power plants, such as Abu Dhabi’s Shams 100 megawatt power project. For Glasspoint, the technology was ideal for heavy oil extraction. This dense oil is often difficult to pull out of the ground. The American firm began seven years ago to create an enclosed solar technology that could produce steam. The next year, the company secured financing to take this advancement to the oil industry.

Glasspoint’s president and chief executive, Rod MacGregor, said that 60 per cent of a company’s operational spending was on fuel for steam generation. However, the sun can deliver steam for less than it would cost through natural gas.

Solar’s cost advantage varies by location and the price of fuel, but it was a “substantial amount” less.

Glasspoint is constructing the 1-gigawatt Miraah thermal solar power plant with PDO, which will be 100 times larger than the pilot facility. “We have proven solar EOR technology, which is designed for the unique needs of the oil and gas industry,” he said.

The latest project will deliver more than 1GW of peak thermal energy, generating 6,000 tonnes of steam a day, which will be used in PDO’s thermal EOR operations to extract heavy oil at the Amal oilfield. The gas that is saved could be used to provide residential power to over 200,000 homes.

The next stop is potentially Kuwait, given that the market opportunity there is in the tens of gigawatts. The firm has a subsidiary located in the country, and has already started to see strong interest in using solar EOR technology. Mr MacGregor added: “Using solar at the oilfield will greatly help Kuwait achieve its plan of generating 15 per cent of the country’s energy needs through renewable resources by 2030”.

Here’s what makes Glasspoint’s technology so much cheaper than gas and also cheaper than electricity-generating CSP:

There is actually no power block at all. No turbines, no heat exchangers, just mirrors to focus the sunlight on to pipes to carry the boiling water and create steam.

While any fossil fuel has to be burned in order to boil water in a power block to make steam, in Mirrah, it is just the passive action of the sunlight reflected and focused by the parabolic trough onto the pipes that is sufficient to boil the water in the pipes to create steam, which is then injected into the oil wells to push out the last dregs of oil.

Higher steam temperatures are needed for electricity generation, but the 310°F steam Glasspoint makes with no power block is perfectly adequate for EOR (enhanced oil recovery). The Miraah project comprises 36 independent, standalone, 50,000 square meter greenhouses that can be deployed as single units or in multiples.

Because the parabolic troughs are sheltered inside the greenhouses, they don’t need to withstand corrosive sand or high winds. So they are just 10% of the weight of regular parabolic troughs, which makes them cheaper.

Glasspoint also saves money by putting the super light parabolic troughs inside standard commercial greenhouses. Standard robotic cleaners also clean the exterior glass at night to keep it at optimal clarity.

Other big solar thermal projects that are not oil related

Santa Monica–based SolarReserve has just announced its gigawatt-scale Sandstone Energy 10X (10-tower) project in Nevada, a 2 gigawatt (GW), $5 billion CSP project expected online in 2021.

At 2 GW (2,000 MW) Sandstone will have 20 times the capacity of its current 110 MW Crescent Dunes project. This raises dispatchable solar to the scale of the Hoover Dam, Nevada’s other ambitious gigawatt-scale renewable generation.

In May: SolarReserve signed MOUs in China to develop 2 GW of CSP towers in a joint partnership with two large generators in China, including the Shenhua Group, China’s largest coal company. (Other than the solar-harvesting heliostat field, a CSP plant is identical to any other thermal plant in its “back end” power block, so there are many opportunities to apply coal-plant building expertise to CSP construction.)

In September: SolarReserve proposed an 800 MW, six tower CSP project at Port Augusta in Australia, where a coal plant closing has left locals rooting for this CSP proposal to replace those coal plant jobs in an unusual example of reverse-NIMBYism.

SOURCES- Cleantechnica, The National