Something Old is Getting a Lot of Attention

Chris Evanich, manager of microgrids, S&C Electric

Globally, we are seeing a push to lower our carbon emissions. From electric cars to rooftop solar, there are more and more ways everyone can help contribute to this goal. While many individuals have personal goals to shrink their carbon footprint, some states have gone as far as setting goals to receive 100% of their power from renewable generation in the next 10-20 years.

Renewable generation is often paired with microgrids, but 100% renewable microgrids are expensive. And in most cases, the generation mix can’t make a strong business case on its own.

An industry trend we have been seeing is to design a microgrid with a mix of renewable and some form of gas generation, often a diesel gas generator. Diesel generation is effective, but it’s not the best option available to pair with wind and solar.

That’s where natural gas comes in. At the end of last year, the United States became the world’s largest natural gas producer, bringing the cost of this fuel source down and making it more readily available domestically. Production has increased so significantly, liquid natural gas terminals are being constructed in the Caribbean, where 90% of the countries have generation from oil.

Renewable sources, even when paired with energy storage, can’t always provide the continuous power a system needs, and natural gas generators can help bridge that gap. Natural gas generation also is providing new options for power users, and it has a bright future in the microgrid industry. As a cleaner, less-expensive fuel option, we should expect more natural gas generators to be added to the generation mix moving forward. These generators perform as effectively as diesel, but at a lower cost.

Among the largest challenges with 100% renewable generation are the ever-present peaks and valleys of demand and production, and often the two don’t meet up nicely. The addition of  natural gas generation not only allows for a continuous source to help even out the power supply, but it also opens the door for new operations within the microgrid. Natural gas generation can also be used for combined heat and power (CHP) applications, maximizing the energy output from this fuel source by allowing for a heat recovery.

So often we view microgrids as an opportunity to improve the grid’s reliability, but with the addition of natural gas generators, they can also help by providing greater resiliency to the system. In a scenario where a microgrid’s wind, solar, or energy storage capabilities are interrupted, natural gas could serve as a reliable backup, ensuring the microgrid can continue carrying the load with no interruption.

Moving forward, natural gas will become a regular component of microgrid generation. Everywhere we look, utilities, companies and individuals are looking to lower their carbon emissions and making a transition to natural gas is one way to help the cause. The great news here, is that natural gas generators aren’t a theory.

We are already seeing advanced microgrids, such as the ones operated by Ameren and North Bay Hydro, using natural gas in place of conventional diesel generators. When designing a microgrid, don’t forget to look to natural gas as a feasible option to lower generation costs and provide greater resiliency to the system.

Chris Evanich is manager of microgrids at S&C Electric.