Reusing old oil and gas sources can offer a solution for green energy storage storage
Moving from fossil fuels to renewable energy sources such as wind and solar energy require better ways to save energy before use when the sun does not shine or the wind is not winding. A new study by researchers from Penn State showed that benefit from natural geothermal heat in exhausted oil and gas sources can improve the efficiency of one proposed energy storage solution: Compressed Air Energy Storage (CAES).
Caes plants compress air and store it underground when energy demand is low and extract the air to create electricity when demand is high. But start -up costs are currently limiting the commercial development of these projects, the scientists said.
The researchers stated a new geothermal assisted energy storage system for compressed air for that use of exhausted oil and gas sources – the Environmental Protection Agency estimates that there are approximately 3.9 million in the United States – and discovered that it could improve efficiency by 9.5% compared to the existing technology. This means that a larger percentage of the energy stored in the system can be restored and can be converted into electricity, making it possible to stimulate the profit for operators.
“This improvement in efficiency can be a game change party to justify the economy of compressed energy storage projects,” said Arash Dahi Taleghani, professor Petroleum and Natural Gastechniek to Penn State and corresponding author in the study. “And moreover, we can considerably avoid the preceding costs by using existing oil and gas sources that are no longer in production. This can be a victory, profit situation.”
Reusing exhausted oil and gas sources would enable operators to gain access to geothermal warmth in underground hot rock formations, which eliminates the costs in advance for drilling new wells and making technology more attractive for industry, the scientists said.
Gases such as compressed air increase in pressure as the temperature increases, which means that, according to Taleghani, the heated wells may be able to store more energy. When electricity is needed, the heated, compressed air is released, driven a turbine to produce electricity.
“Without taking advantage of the geothermal arrangement, you could not get enough encouraging figures,” Taleghani said, and explained that the team used numerical modeling simulations to discover that placing CAES systems in abandoned oil and gas sources considerably increased in the systems. “And moreover, drilling new wells cannot justify the economy of this type of storage. But by combining these two factors, and by going back and forth by modeling and simulation, we thought this could be a very good solution.”
Options for energy storage such as CAEs are especially important in the transition to clean energy, according to the researchers, because they help to tackle the intermittent nature of renewable sources. By storing surplus renewable energy and when needed, energy storage contributes to raster stability and reliability.
“The problem is that when we need energy, there is no sunshine or there is no wind,” Taleghani said. “That is a big barrier against further expansion of the most renewable energy that is available to us. That is why it is very important to have some storage capacity to support the grid.”
Rewing of exhausted oil and gas sources can also help to reduce possible environmental effects of abandoned wells and offer possible new vacancies in areas with rich traditions in the energy industry, the researchers said.
In Pennsylvania alone, regulators estimate that there are hundreds of thousands of or abandoned wells. If these wells are incorrectly connected or damaged, they can leak methane in the atmosphere and groundwater.
“If we use existing wells, we actually touch two birds with one stone,” Taleghani said. “First of all, we are sealed these wells. That stops possible leaks. And then when we re -use these wells for energy storage, we still use the infrastructure that is present in these communities. It may be able to enforce work in the area and enable communities to be part of the Energy Fair.”
This research was carried out as part of the REVIOUNT CENTER for Energy Transition (Recet) in Penn State. The center aims to reuse the infrastructure of fossil energy for energy transition applications, in particular in Legacy energy communities.
Also contributed from Penn State was Derek Elsworth, G. Albert Shoemaker chairman in mineral engineering and professor of Energie and Geo-Envisginering, and Qitao Zhang, a post-doctoral scholar, both in the family of John and Willie Leone Family and Mineral Engineering.
Research report:Underground energy storage using deserted oil and gas wells assisted by geothermal