By Stuart McCafferty and Kevin Brown
Back in January, GridIntellect’s Chief Scientist, Kevin Brown, and I were approached by the National Electrical Manufacturers Association (NEMA) to pen an article on MicroGrids. If you read through all our blogs, you know that we have some opinions and pointers on a variety of smart infrastructure modernization topics, but mostly on MicroGrids. Later that month, Kevin and I sat down over a few frozen margaritas in beautiful Marathon, FL (while everyone else in the country was FREEZING) and we talked about a lot of different topics, but mostly about DC power, renewables, and (of course) MicroGrids.
Both Kevin and I love utility companies. They not only provide very reliable and affordable AC power, they have also been the source of a good portion of our consulting business over the years. We are also huge fans of renewable energy and storage primarily due to their environmental and resiliency/sustainability benefits. So, if you listen to the standard opinions of others, these are opposing, almost mutually-exclusive thought processes. We just simply don’t believe that. We believe that if you start at the loads and use them to determine the optimal generation resources, the solution becomes self-evident and fully supports a coexistence paradigm that benefits all parties – utilities, end users, renewable energy advocates, independent power producers, and regulators.
AC power is wonderful. Utilities provide lots of it reliably and at a very reasonable cost. If you have equipment that spins, has an element, or compresses something, it is the best possible solution. So, air conditioners, filament lighting, compressors, heaters, and pumps are natural loads for AC generation power sources – and it comes straight to your home or business in ample quantities most of the time.
DC power is wonderful, too. Solar panels and batteries provide native DC power. If you have equipment that is electronic, it is the correct solution. So, computer equipment, home entertainment equipment, and LED lights, are natural loads for DC generating equipment. This article describes a conceptual architecture and approach that suggests sizing your renewable energy generation project to only address the needs of the DC equipment. This allows both utilities and renewable power to coexist in mutually-beneficial ways. Utilities can reduce or eliminate their expensive (and sometimes environmentally-unfriendly) peaking power plant needs and tap into clean energy distributed generation. Renewable energy users can reduce the costs of construction and maintenance since their needs are restricted to just the DC loads. The solution is also more efficient since lossy DC-AC and AC-DC transformations are reduced or even eliminated in totally ideal situations. And, rooftop solar becomes a compelling solution for a lot of buildings.
Yes, there are some challenges to overcome, but the concept is pretty simple, practical, and a win-win for both utilities and end users. NEMA published our article in the June 2014 edition of its electro-industry magazine. Read on below to chew on the idea. Maybe someday this is how everyone will approach their energy needs and the utility doomsayers will have to sit back and smile as the utility business continues to thrive and even grow as the overall energy needs for end users continues to grow over time.