A Powerful Combination: Blending the Benefits of Renewables and Diesel in Microgrids
Darren Tasker, vice president of industrial sales at Volvo Penta of the Americas, discusses the benefits of blending renewable energy sources with diesel generators in a microgrid.
Governments across the globe are calling for an accelerated transition to decarbonization and increased integration of renewables into energy systems. While much of the conversation naturally focuses on emerging technologies such as solar, wind and battery, the reality is that diesel solutions will continue to play an important role in the microgrid energy strategy mix for years to come. So, what are the benefits of combining renewables and diesel-powered generators within an integrated microgrid solution?
Most microgrids use some combination of solar/wind, battery storage and diesel power to deliver electricity to remote locations. A diesel-powered generator provides backup power when the wind doesn’t blow, or the sun doesn’t shine, or when batteries become depleted.
Diesel power provides reliability that supports electrical loads when renewable energy and battery power cannot. With every system, there will come a time when battery power is insufficient, but the operation still needs power. An internal combustion engine provides instant power for extended periods of time, making it an essential part of most microgrids.
Seamlessly switching from renewable energy to diesel power and back again involves a control system. This technology monitors the amount of energy produced by the microgrid and makes sure energy from renewable sources gets stored in the system’s battery bank. It also tracks electrical demand from the operation. When the system detects a potential power shortage, the controller turns on the diesel-powered generators to fill identified needs. The system manages these transitions seamlessly without operator intervention.
Given the current state of technology, these systems will need to be grossly oversized unless the microgrid utilizes a generator driven by an internal combustion engine
Source: Volvo Penta, courtesy of PowerSecure
Here are some facts and benefits of blending renewable energy sources with internal combustion engines in a microgrid:
- Lower emissions: Diesel-powered gensets operating in US microgrid applications are required to be Tier 4 Final certified by the EPA and CARB. Tier 4 Final diesel engines, like those from Volvo Penta, use low-sulfur diesel to reduce emissions of harmful gases into the air. The systems are designed to operate efficiently and emit less carbon dioxide, nitrogen oxide (NOx) and particulate matter, reducing their carbon footprint. In fact, the Diesel Technology Forum, a nonprofit advocacy group for diesel technology, finds Tier 4 Final engines can reduce NOx and fine particulate emissions by up to 90% compared to earlier engine technologies.
- Reduced fuel use: A microgrid that blends renewable energy with diesel power can trim fuel costs. It’s more economical for an operation to generate its power needs from renewables, while coupled with a significantly downsized diesel-powered generator.
- Smaller footprint: A microgrid that only uses renewable energy sources will need a sizable battery bank to store power generated by these sources to meet the demand. Space limitations and budget may prevent operations from adding a large enough energy storage system. Adding in diesel power eliminates these concerns. The generators activate when renewable energy sources are low.
- Redundancy: Using multiple types of energy builds in redundancy. If one source is low, the others are available.
- Instant electricity: Diesel engines provide instant electricity when renewable energy or battery power isn’t available. There’s no need to halt operations and wait for the microgrid to produce needed power. A blend of technologies produces all the electricity the operation needs.
- Joined generators: It’s possible to join generators together to synchronize and load share. Joining multiple generators allows users to turn on one or two generators to produce needed energy and save money. Plus, running engines with at least a 60% load is best from an emission, efficiency and longevity perspective. It’s also possible to stack engines when space is at a premium.
- Better ROI: In certain circumstances, the cost of generating electricity from a microgrid can be lower than the utility cost. As energy costs increase over time, your investment into a microgrid that includes a Tier 4 Final powered generator has potential to pay for itself even faster.
A microgrid solution that pairs renewable energy with generators powered by Tier 4 Final engines will be efficient, flexible and have lower emissions. It’s the best of both worlds and a powerful combination. Operations get access to the power they need while meeting demands for greater sustainability, lower emissions and optimized fuel use.
Darren Tasker is vice president of industrial sales for Volvo Penta of the Americas.
