Air pollution and global climate change have become important environmental issues in international politics and daily life. Some technologies have been introduced that could reduce the amount of air pollution going into the atmosphere, while other technologies address climate change by tapping into intermittent renewable energy sources such as solar or wind. Unfortunately, these technologies do not address existing industry issues that continue to contribute to both air pollution and climate change. Current industry infrastructure – from landfills to coalmines, and from oil and gas to agriculture – pollute the air with gases such as carbon dioxide (CO2), nitrogen oxides (NOx) and hydrocarbons such as methane (CH4). While there has been much focus on carbon dioxide, policy in the US and Europe is beginning to shift its attention to ways of mitigating the harmful emissions of hydrocarbon gases such as methane.
Cubic metres of methane humans put into the atmosphere each year
Of greenhouse gases are anthropogenic methane emissions
Methane is one of the most dynamic and important chemical compounds on Earth. It can heat our homes and fuel our power plants when it is harvested correctly and efficiently. However, methane traps 20-25 times more heat (within our atmosphere) than carbon dioxide. Hence, when mishandled or ignored, methane becomes an important catalyst for global warming. The US Environmental Protection Agency (EPA) estimates anthropogenic activities release over 480 billion cubic meters (bcm) of methane emissions into the atmosphere each year. This is equivalent to over 20 percent of global greenhouse gas emissions.
Many industries currently rely on flaring to burn waste gases in order to prevent greenhouse gases such as methane being released into the atmosphere. The World Bank Global Gas Flaring Reduction partnership estimates 150bcm of gas is being flared annually. If one were to compare that to the gas production of each country in 2011, flaring would be the sixth largest producer, between Canada and Qatar. Unfortunately, flaring is an incomplete solution for mitigating methane emissions, as it only partially destroys the gas and creates additional pollutants such as smog-forming NOx. Flaring inefficiently wastes this potential energy resource, while continuing to pollute our air.
Ener-Core, a clean energy business based in California, has developed its patented gradual oxidation technology as an innovative alternative to flaring and venting, turning these potential sources of pollution into energy resources. Ener-Core’s gradual oxidiser is paired with a gas turbine, and enables the turbine to directly convert these wasted gases into electricity. With the Ener-Core technology, the 150bcm gas being flared each year could instead be turned into over 20,000 MW of power (enough energy to supply power to 20-30 million homes) with the added benefit of avoiding smog-forming NOx.
Converting pollution to clean energy
When many waste gases are produced, they typically have such a low energy density and/or such a high level of contaminants that standard power generation systems (such as reciprocating engines and gas turbines) cannot adequately utilise them. Industry’s next alternative is to feed these waste gases to flares, burning the gases at high temperatures in order to reduce the amount that gets released into the atmosphere. If the energy density of gas is too low for simple burning, then the industrial site must purchase supplemental natural gas (or propane) just to raise the energy density to the level where the gas can be burnt, thus creating a cost burden. This scenario is quite common within refineries and chemical plants as they attempt to destroy the volatile organic compounds (VOCs) that are produced by their normal operations.
Ener-Core’s gradual oxidation method allows for the productive use of some of the most difficult and unusable industrial waste gases
Ener-Core’s innovative gradual oxidation method allows for the productive use of some of the most difficult and unusable industrial waste gases. In nature, virtually all gases that are emitted into the atmosphere will go through a chemical oxidation reaction, but the natural reaction takes years. Ener-Core has managed to take this naturally occurring oxidation reaction, and compress the reaction time to one to two seconds. The reaction is contained within a vessel, so a precise amount of heat energy at pressure is released. The gas turbine prime mover can then harness that pressurised heat energy to turn the generator, which generates electricity and feeds it back to the industrial facility or out to the utility grid. Through Ener-Core’s technology, these gases that were previously useless have become a potentially abundant source of energy, turning zero value waste gases – even VOCs worldwide – into a revenue stream for the companies that produce them. This enables traditional industrial processes to generate power from waste gases while simultaneously meeting strict environmental policies; Ener-Core’s system is able to achieve rates as high as 99.8 percent destruction of contaminants in the gas stream and reduce NOx emission to as low as one part per million.
Looking towards a cleaner future
Going as far back as the Industrial Revolution, most of the world’s energy has been generated by combustion-based processes. Combustion is useful for high quality clean fuels, but unfortunately ineffective on many of the poor quality gases created by industry. Ener-Core aims to repurpose what has, for 200 years, been considered waste. Instead of using cost-burden technologies such as flaring and venting, Ener-Core systems supply an air pollution control that pays for itself through the generation of clean energy. In the US alone, unused sources of methane from landfills could generate as much as 2,400 MW of continuous base load renewable energy. That would be the equivalent output of 10 average capacity coal plants, while mitigating the impacts of methane and CO2, and eliminating almost all of the associated, hazardous, smog-forming NOx.
Ener-Core has recently begun commercialising this technology, after successfully completing a one-year field demonstration project at a US Department of Defense base in Fort Benning, Georgia. Ener-Core’s 250 kW technology has now been commercially deployed in the Netherlands at Attero’s Schinnen landfill, generating renewable electricity and reducing emissions. Ener-Core is now scaling up its technology to pair with the Dresser-Rand KG2/3G turbine. The larger scale product (1.8 MW) that results from this pairing offers even greater value, generating energy worth up to $2m each year. Over time, Ener-Core will continue to pair its technology up with larger turbines that are available in the market.
Ener-Core is transforming the way people think of and use waste gases. The gradual oxidation technology can be applied to virtually any industry worldwide that produces and then flares or vents waste gases into the atmosphere. Ener-Core estimates there is at least 65 GW of power capacity that could be generated from waste gases; turning a zero value costly pollution source into a site revenue stream. Alain Castro, CEO of Ener-Core, says: “The size of this market is about $70-100bn of equipment that could be sold to utilise these low quality gases.”
The looming issue of global warming requires tomorrow’s technology today. Stephen L Johnson, the 11th Administrator of the EPA once said: “If we as a society really wish to embrace sustainability, then we should embrace technologies that can make sustainable practices profitable.” Ener-Core was founded on the idea of merging both business realities and considerations with environmental consideration and consciousness – helping to solve a real global problem in a profitable manner.