Why Every Microgrid Should Contain a Natural Gas Generator: A Sustainable Solution for Uninterrupted Power Supply

A microgrid is a localized group of electricity sources and loads that can operate independently of the traditional centralized power grid. Microgrids can include a variety of different power sources including renewable energy resources.

Typically, a microgrid consists of several essential components some of which are listed below:

• Energy generation resources like; solar panels, wind turbines, fuel cells, D-UPS, diesel generator, or natural gas generators.

• An battery energy storage system, BESS, to store excess energy and provide power when the solar and wind cannot.

• A load (typically the group of electricity consumers on the microgrid).

• A microgrid controller that controls and optimizes the generation, consumption, and storage of energy.

• A controller and switching system that enables the microgrid to switch between operating in utility-connected or island mode.

• An advanced communication system that enables the coordination and optimization of the microgrid’s elements.

Microgrids offer many benefits, particularly for businesses and institutions. We have listed five below but there are many more depending on the unique site situation:

• Resilience and Reliability: Microgrids can operate in island mode during a grid outage, providing uninterrupted power supply which means uninterrupted business operation.

• Energy Efficiency: By generating power close to the source of consumption, microgrids reduce transmission losses.

• Cost Savings: Microgrids can provide 100% of the power required for your facilities or they can leverage peak shaving and load shifting strategies to lower energy costs (or a combination of these solutions). Some microgrids can also produce power to the utility grid and become revenue generators.

• Environmental Sustainability: By incorporating renewable energy sources, microgrids reduce greenhouse gas emissions (especially if the utility power uses a combination of coal fired power generation). This plays in big role in a business as they drive towards their net-zero or carbon-neutral goals.

• Energy Security: Microgrids reduce dependence on the national grid, enhancing energy security.

Despite the promise of renewable energy sources like solar and wind, their intermittency and low capacity factor (1) makes it difficult to rely on them exclusively for a consistent power supply. This is where natural gas generators become invaluable. A natural gas genset can be brought online by the microgrid controller to provide power when renewable resources are not available, such as when the sun isn’t shining or the wind isn’t blowing. See MIT Energy Initiative’s study; “The Future of Natural Gas” (2) for more details.

Comparing natural gas generators to traditional diesel generators, natural gas has several advantages:

1. Lower Emissions: Although emissions vary greatly between manufacturer and generator size, natural gas generators produce fewer emissions than diesel, including lower CO2, NOx, VOC, and particulate matter emissions (3), which makes them a cleaner alternative (International Energy Agency, 2021 (4)).
2. Cost-Effectiveness: Natural gas is more cost effective than diesel, resulting in lower operating costs.
3. Reliability: Natural gas supply is usually more reliable than diesel especially in urban areas with established natural gas infrastructure. Diesel tanks need to be filled while methane is “unlimited” via a natural gas pipeline.

Regardless of the technology chosen for your microgrid, there is a capital cost required to get a system designed, installed, commissioned, and started up. Many companies simply don’t have the capital sitting around for this type of investment and continue to rely on unreliable and expensive grid power. However, this is where Energy as a Service can play a role in getting your microgrid system in place and removing your reliance on the traditional power grid.

EaaS – Energy as a Service

Energy as a Service is essentially the supply of key components of a microgrid system on a lease type arrangement or power purchase agreement. This allows customers to avoid the upfront capital cost of purchasing these key components.

The key components of EaaS that Collicutt Energy is able to provide include;

• Microgrid controllers
• BESS systems
• Gas generators
• Biogas generators
• Gas blending systems
• D-UPS units
• Diesel generators (for black start)

Summing Things Up

In conclusion, the integration of natural gas generators in a microgrid design is a practical, sustainable, and economical solution for ensuring uninterrupted power supply. As businesses and institutions continue to strive for resilience, efficiency, and sustainability, the microgrid—with natural gas as a key component—presents an effective pathway to achieve these objectives.

If you have any questions regarding this article or if you have a microgrid or power project of any kind give us a call at Collicutt Energy at 888.682.6888. We have a team of experts that would be happy to work with you to evaluate your project and determine the best fit solution for you.

Why Power Density Makes Natural Gas Essential for Every Microgrid

Defining Power Density

Power density, typically measured in Watts per kilogram (W/kg), refers to the power created per unit of material required to produce that power. It provides a metric for assessing the resource intensity of various power generation methods.

Essentially, a high W/kg rating means that the power generating device creates more power per kilogram. A low W/kg rating means that it takes more material (e.g., cost and complexity) to create a Watt of power.

Comparing Power Densities of Various Energy Sources

The following chart is a screen shot from the International Energy Agency (1) and it illustrates the vast difference between the mass of material required to produce a unit of power for various energy sources. This chart is shown in kg/MW to illustrate the amount of specialty materials required to generate a MW of power.

If we take the inverse of these numbers, we get the power density graph that is shown below in W/kg.

As you can see, natural gas power generation has the highest power density of the six power sources shown. In fact, it has approximately 5.5 times more power density than solar PV and approximately 13 times more power density as offshore wind power!

Besides taking less mass to produce a unit of power, natural gas power generators have a smaller footprint, can be placed almost anywhere in a microgrid system, and can be designed to have a relatively fast ramp up time.

From the above, it’s evident that while renewables like solar and wind may be important for a sustainable future, their lower power densities mean they require more substantial physical footprints to match the output of fossil fuels. This is where the strategic use of natural gas can provide a balance.

Why Power Density Matters for Microgrids

Microgrids, especially those serving urban areas or critical facilities, often don’t have the luxury of vast expanses of space. Thus, power density becomes a critical consideration. Natural gas generators, with their high power density, can deliver significant power from a compact infrastructure, making them especially suited for space-constrained microgrids.

Moreover, natural gas generators can efficiently address the intermittency of renewables. On days when the sun isn’t shining or the wind isn’t blowing, the high power density of natural gas can ensure that the microgrid’s energy demand is met.

Conclusion

Power density is a pivotal metric when planning a microgrid’s energy mix. While renewable energy sources bring benefits, their lower power densities necessitate complementary power sources with a compact footprint and high output. Natural gas generators fit this bill perfectly, making them indispensable for microgrids aiming for resilience, efficiency, and sustainability.

If you have any questions regarding this article or if you have a microgrid or power project of any kind that could benefit from a methane powered generator, give us a call at Collicutt Energy at 888.682.6888. We have a team of experts that will work with you to evaluate your project and determine the best fit solution for you.

Flexibility of Methane-Fueled Power Generation

Selecting an energy source for electricity generation requires careful consideration of various factors including flexibility of the fuel source. Although this is far from an exhaustive list, flexibility factors have to include things like; ease of access, affordability, safety, and transportability. These factors are described in more detail below.

Ease of Access

There are two main components of ease of access that we will cover here:

• Availability:

  • Methane is a prolific fuel used all over the world for heating, transport, and power generation. As with any fossil fuel, the source is not infinite, but many estimates suggest there is at least 52 years or more left of fossil-based methane (1).

• • Hydrogen does not exist naturally in nature like hydrocarbons or coal so it must be manufactured. Hydrogen can be produced in a number of ways (e.g., electrolysis, coal gasification, biomass gasification, hydrocarbon processing, etc. (4)) but it is a manufactured gas that “takes energy to produce energy” (6) (7). The energy required to produce hydrogen means that it costs more to produce (see notes below on affordability). It is also complicated to produce, store, and transport so it has been slow to become adopted as a mainstream fuel.

• Existing Infrastructure:

  • There is already a well-established infrastructure for methane extraction, storage, transportation, and distribution in North America and most of Europe. Natural gas pipelines, refinement, and storage facilities are abundant, allowing for reliable and widespread access.

• • There is little to no infrastructure existing in the world today for hydrogen gas supply to the everyday consumer. For example, there are approximately 1.5 billion cars on the earth today (2) and only 11,200 of those are hydrogen powered (3). The infrastructure that is in place is not built for hydrogen and will take significant investment to allow for that fuel changeover. This is reinforced by the National Renewable Energy Laboratory website (8) which states; “Hydrogen has very high energy for its weight, but very low energy for its volume, so new technology is needed to store and transport it.” Building out an infrastructure that will support the use of hydrogen as a consumer fuel is just getting started (5) and will probably take decades to achieve.

Affordability

Because methane is an abundant fuel, it is generally affordable in the western world. Pricing and availability can be impacted by weather or geopolitical events but methane is typically an affordable fuel even if it is transported long distances including via ocean transport (see below for more details).

Conversely, as mentioned above, hydrogen does not exist naturally in nature, so it must be manufactured. This manufacturing process takes energy and creates green house gas emissions. As per the National Renewable Energy Laboratory website (8); “Most hydrogen production today is by steam reforming natural gas. But natural gas is already a good fuel and one that is rapidly becoming scarcer and more expensive. It is also a fossil fuel, so the carbon dioxide released in the reformation process adds to the greenhouse effect.” New and more effective ways of hydrogen production are underway but this will take time before it is an affordable fuel.

Safety

There are inherent dangers with the use of any fuel. For example, there is a risk, albeit small, that your gasoline tank on your car may explode in an accident, or that your electric car battery may ignite due to a battery fault, or that a natural gas pipeline may be ruptured by a backhoe. However, each of these “fuel systems” have had many years of refinement and have built in safety designs that now result in extremely safe use of these fuels with very few incidents.

Conversely, there is very little history yet with hydrogen fuel in the marketplace. As per the above quote taken from the National Renewable Energy Laboratory, ” . . . new technology is needed to store and transport it. And fuel cell technology is still in early development, needing improvements in efficiency and durability.” The technology development is underway but it will take time to implement it and refine it to the level of safety currently seen with methane.

Transportability

When it comes to transportability, the infrastructure in the western world for methane is well established with well sites, hydrocarbon processing facilities, pipelines, LNG facilities, etc.

This infrastructure does not yet exist for hydrogen and is still in its infancy. As we can see below, the inherent properties of hydrogen impose some transportation limitations and inefficiencies that add cost and complexity.

In comparing ship-based methane transport to ship based hydrogen transport, hydrogen takes 2.5 times the tanker space to transport the equivalent energy value (in this case 1 TWh). In addition to this, hydrogen boils off at a rate of 1% per day during transport while methane boil off rate is one-tenth of that.

Diagram from Michael Sura depicting the difference in hydrogen vs methane boil off rate.

Similarly, ground transport challenges for hydrogen transport are illustrated in the following diagrams (again sourced from Michael Sura (9).

Conclusion

After careful examination of the flexibility of methane as a fuel source compared against hydrogen, it seems that methane comes out ahead in each of the categories that were examined:

• Ease of access
• Affordability
• Safety
• Transportability

In conclusion, when the flexibility of methane as a fuel is factored into a decision matrix along with EROEI conclusions from Part 2 of this series and the GHG emissions conclusions from Part 1 of this series, one must seriously consider the responsible use of methane as a fuel for electric power generation.

If you have any questions regarding this article or if you have a microgrid or power project of any kind that could benefit from a methane powered generator, give us a call at Collicutt Energy at 888.682.6888. We have a team of experts that will work with you to evaluate your project and determine the best fit solution for you.