Imagine a Venn diagram with two overlapping circles labeled “solar power” and “microgrids.” In the solar power category, you’ve got gigawatts being pumped out around the globe, ranging from utility-scale solar plants to residential rooftop PV arrays, and everything in between.
In the microgrid category, you’ve got a motley collection of off-grid installations for remote applications like oil wells and cellular towers, uninterruptible backup power systems for critical infrastructure like hospitals and military bases, and in the case of places like India or Africa where the grid is unreliable, thousands and thousands of diesel generators chugging away when the power goes down.
Almost none of these microgrids run on solar power, and those that do tend to be experimental projects like the U.S. Department of Energy’s SEGIS program participants, or Japan’s Smart City Projects. Private projects that actually make and store enough solar power to keep themselves running are rare.
Among the companies that sit at the intersection of these solar and microgrid worlds is OutBack Power. The Arlington, Wash.-based company, founded in 2001 as a maker of “pure sine wave” inverter products, has since expanded to grid-tie and off-grid inverters, maximum power point tracking charge controllers, communications and network products and integration hardware to keep it all working together.
In 2010, OutBack was bought by The Alpha Group, a Bellingham, Wash.-based maker of AC and DC power conversion, protection, standby and renewable energy products, including batteries. Since then, OutBack has launched a lot of new products aimed at providing clean and reliable power for applications, from U.S. Marine Corps combat vehicles and remote posts, to clean power for solar-backed concerts -- and grid-tied solar-powered microgrids like the one it built for Malankara Plantations, an historic rubber plantation compound in Kerala, India.
That last project -- a 27-kilowatt solar and inverter array -- is one of the first “net-zero” buildings in India, meaning that over the course of a year, it generates more energy than it consumes from the grid. But it’s also designed to run completely off-grid, which is important for protecting the 45-employee office from the far too common power outages that plague India’s grid infrastructure, as last week’s 600-million-person blackout highlighted.
Compared to the major solar inverter players like SMA, Fronius, Advanced Energy, Kaco, and Satcon, the scale of OutBack’s installations isn’t that large. GTM Research has estimated the solar PV inverter market stood at $6.9 billion in 2011, and while OutBack doesn’t disclose figures on its deployments, it’s sure to add up to a tiny fraction of that overall market.
But Mark Cerasuolo, OutBack senior marketing manager, sees the skills the company has learned in its microgrid projects becoming increasingly important to the broader solar industry. “The off-grid smarts, reliability and capabilities that we’ve done traditionally, have become central to the grid-hybrid space,” he said in an interview last week.
Projects that merely hook solar power to the grid via inverters are “kind of one-trick ponies,” is how he described it, while grid-interactive systems are “more like a three-ring circus -- it’s managing energy, it’s managing energy storage, and it’s managing the grid.”
Of course, there’s an additional cost that comes with backing up your solar array with energy storage, or smart inverter controls that can order on-site generators to kick on when the solar power isn’t quite meeting your local demands.
Cerasuolo estimates that systems that add emergency power backup run 15 percent to 20 percent higher, while systems with lots of backup capacity -- say, enough to keep an ordinary business or facility running off the grid on a regular basis -- will add 30 percent to 40 percent to those costs.
When is that extra cost worth it? For remote industrial or military applications, the answer is clear: without batteries or local generators, it won’t run at all. That makes the remote microgrid market a natural target for the likes of SAIC, Lockheed Martin, Power Analytics (formerly EDSA) and other military specialists. General Electric is doing a big microgrid project with the U.S. Marine Corps.
Similar imperatives apply to systems built to provide power in an emergency, such as the work it’s doing with the Florida Solar Energy Center. OutBack is helping the state energy office outfit about 60 schools in the state as emergency shelters for use during disasters like hurricanes, Cerasuolo said.
For the time being, OutBack sees its mission as “bringing power to parts of the world where it’s not available or reliable,” he said. That means that growth for systems that allow backup power and microgrid functions is “going to be very very uneven, depending on the region you’re in,” he said.
But even for grid-connected systems, being able to optimize a mix of on-site generation, energy storage and solar power can help customers manage their power use -- and thus, power bills and payback on their solar investments -- in a more effective manner, he said.
The entire solar industry is moving towards closer integration of advanced inverters, energy storage and remote monitoring and management technologies with solar panels. On the inverter side, Germany is requiring new solar inverters to perform certain functions, such as power ramping and volt/VAR control, while in the United States, startups like Petra Solar are combining solar panels and smart inverters in modules that utilities or end users can deploy for stable, grid-supporting green power.
As for energy storage and solar, we’re seeing combinations being promoted by vendors such as SolarWorld, Samsung, BYD, Aleo Solar, centrosolar, Bosch/Voltwerk and Kyocera. Partnerships like those between General Electric and Arista, Tesla and SolarCity and Silent Power and Hanwha are trying to bring battery-backed solar to a grand scale.