“Microgrids have really come of age,” said Guidehouse Research Director Peter Asmus in his opening remarks to a global audience at the ninth annual HOMER Microgrid and Hybrid Power International (HMHI 2021) virtual conference, Oct. 12–14, 2021.
Participants from more than 120 countries joined sessions and connected across locations including Argentina, Australia, Cambodia, France, Germany, Kenya, the Philippines, Rwanda, Togo and Uruguay. Six conference sessions explored a broad spectrum of the microgrid industry, including engineering, business innovation, policy and regulation. Speakers from industrial and developing countries presented case studies for microgrid applications that range from large U.S. hybrid power plants to direct current (DC) mesh microgrids in remote Cambodian villages.
Hybrid power systems showcased as the future of energy
In his worldwide market assessment, Asmus cited key trends driving hybrid power adoption. He focused on increased financing opportunities via the energy-as-a-service business model, the emergence of the commercial and industrial (C&I) market as the fastest-growing segment, and the newfound relevance of microgrids to electricity-powered transportation where truck and bus fleets have moved center stage. Not only will electric vehicle (EV) fleets consume huge amounts of electricity, they will also be able to feed energy back to the grid. This innovation would seriously strengthen microgrids as a resource, with the potential to evolve into functional power plants.
UL’s Global Microgrid Lead and HOMER Energy by UL Founder Peter Lilienthal, who has his doctorate in management science and engineering, provided a look at the evolution of microgrids. He traced microgrids from their early use as the power supply for remote villages to the utility-scale hybrid power plants now emerging. “We’re on the verge of a real inflection in energy, and hybrid power systems are the key to unlocking that future,” he said. Explaining that hybrid systems with storage provide both flexibility and resilience, Lilienthal predicted that “large hybrid systems will be instrumental in achieving high levels of renewable penetration worldwide.”
Cameron Brooks, executive director of the new U.S. microgrid advocacy group “Think Microgrid,” described good-news-bad-news progress in opening needed pathways for the development of microgrids. While several states such as New York and California have passed legislation to enable microgrids, he said overall project development has been disappointingly slow. “Microgrids are not coming online at the scale and pace required to meet the challenges of our time,” he said. Brooks recommended regulators and political leaders re-examine traditional utility business models that prioritize capital expenditure on centralized energy projects. He said a continued focus on centralization would penalize customer innovations such as microgrids, and redirection would encourage more distributed energy projects.
Storage investments and utility-scale microgrids reshape the market
In the session on large, storage-plus-renewables front-of-the-meter systems, presenters discussed the technology advancements and declining energy storage costs as a significant incentive for utilities to invest in renewable hybrid power systems. The science of choosing battery systems and then managing and augmenting the degradation of battery storage capacity over a lifetime is evolving, said David Mintzer, UL energy storage lead. Meanwhile, new federal regulations pave the way for storage system owners to participate in wholesale energy markets. In addition, developers now have access to modeling technology such as UL’s HOMER software, which helps reduce financial risks through more accurate up-front cost and maintenance estimates, according to Raafe Kahn, manager of energy storage at Pine Gate Renewables.
As microgrids make their way into the discussion as a viable option for hybrid power systems for utility-supplied power, system designers are reinvigorating the longstanding debate about the relative merits of AC- versus DC-coupled systems. In her presentation, GE Renewable Energy’s Neha Sinha detailed the value of the two types of systems. She showed that more DC-coupled systems are emerging as a viable choice for particular priority alignment, often including tax incentives and energy sales to the grid.
Electric vehicles put microgrids in a new role
The fast-evolving relationship between microgrids and electric vehicles was a new and vital focus for HMHI 2021 — and judging from the numerous questions to presenters, it was one of the more popular topics. Multiple presentations centered on the potential of renewable energy microgrids to meet the growing demand for clean, reliable energy to recharge batteries for electric transportation. Presenters from Rwanda and India compared the economic and technical characteristics of new EV charging infrastructure in projects modeled with HOMER Grid software.
Craig Lewis, founder and executive director of Clean Coalition, and Duncan Campbell, vice president of Scale Microgrid Solutions, presented multi-purpose microgrids incorporating EV charging. Gastón Ortega, business development lead for microgrid and battery energy storage solutions and grid edge solutions at Hitachi ABB Power Grids, discussed an experimental vehicle-to-grid project. A common theme emerged through the presentations: Electrifying transportation will dramatically increase electricity demand. The increased demand will require renewable hybrid power systems to avoid massive increases in carbon emissions.
“Now we are beginning to be aware of the electric vehicle charging load. In 2021 it looks like 25 gigawatts (GW), and in 2030, it is nearing 180 GW,” said Asmus in his keynote address. Asia will be the largest market, followed by Europe, with the U.S. in the third position geographically. He added that the most significant loads would initially be to charge fleets of electric buses and trucks.
New, “smart” microgrid controls decentralize system
One of the fastest-growing areas of the microgrid industry is the development of smart controls that can manage multiple energy resources, paving the way for successful integration with the grid. Presenters described digital devices growing smarter and smaller and control systems for distributed energy resources that are evolving to manage increasingly complex operations. According to Chris Wiacek of PXiSE, control systems use advanced communications protocols to protect expensive equipment, react to weather information, orchestrate voltage and frequency regulation, monitor systems remotely and manage cybersecurity. These systems use battery state-of-charge information to switch resources on and off and determine when to send energy to the grid or consume it on site. Finally, control systems can play a transactive role, too, responding to incoming market prices or utility rate signals to optimize the economic performance of microgrids for investors.
Siemens Energy’s Dino Ablakovic, a microgrid product manager, detailed the benefits and challenges of transitioning from conventional power plants to large, hybrid power plants. He noted that sizeable hybrid power plants require multiple studies on grid code compliance, isolation coordination and custom function tests.
Islands and C&I projects: Microcosms for microgrid innovation
Whether managing power flow between Greek Island wind farms or commissioning a microgrid to free residents from the constant chugging of diesel engines, presenters in the session on island power showed hybrid energy systems could bring clean, reliable power to remote communities at a reduced cost. Around the world, islands continue to install microgrids to overcome the burden of exorbitant diesel costs and increase resiliency in the face of intense and more frequent hurricanes, as presented by the Clinton Foundation’s Leon DeSouza.
Meanwhile, other innovators discussed using HOMER software to experiment with new business models, such as the Rocky Mountain Institute’s presentation on work in Nigeria to help create collaborative agreements between utilities and C&I customers.
On-demand recordings are now available
Complimentary recordings are now available for the ninth annual HOMER Microgrid and Hybrid Power International. We hope to encourage further innovation and contribute to a clean energy future by facilitating the exchange of ideas on distributed energy resources. If you know your password you can access the recordings here. If you need to register for access, please visit our resources page.