In Albuquerque, N.M., a smart grid-solar-energy storage project backed by a consortium of Japanese giants is testing out a key element of the idea of net-zero energy communities: how to harness mass-market solar to balance the grid inside and outside the neighborhood’s borders.
At least, that’s where the idea could go for Mesa Del Sol, a mixed-use redevelopment project with plans for 18 million square feet of office, industrial, and retail space and about 37,000 homes. Forest City, the Cleveland-based property development giant, is in charge of the decades-long development plan, and last week unveiled the first piece of it: the 78,000-square-foot Aperture Center, which has been set up to run on its own solar power.
The event center’s 440-kilowatt peak load will be covered by a 50-kilowatt solar photovoltaic system, an 80-kilowatt fuel cell, a 240-kilowatt natural gas powered generator and a 160-kilowatt-hour battery storage system. The technology -- and funding -- comes via Japan’s New Energy and Industrial Technology Development Organization (NEDO), which is investing about $10 million in the Mesa Del Sol project and another $12 million in another project in Santa Fe.
On the U.S. side, utility PNM, Sandia National Laboratories and the University of New Mexico are on the team. In its entirety, it’s still pretty small, on a par with the many different solar-storage-backup power systems being tested out around the country and the world.
But if it fulfills its promise of smoothly connecting and disconnecting from PNM’s grid -- as well as providing its power to smooth out the grid during times of peak stress -- it could take the claim of the first fully functioning microgrid in the country, said Manny Barrera, Mesa Del Sol’s director of engineering.
And that, in turn, could help developers like Forest City tackle a key challenge of managing all the rooftop solar that they can pencil into their plans, now that solar panel prices and installation costs are plummeting.
Distributed solar is booming, driven by the flood of cheap panels from China and financial innovations like the leasing and financing plans from the likes of SunEdison, SolarCity, SunRun and others. Up to a point, all that two-way power flow from homes and businesses isn’t too disruptive to utility operation. But higher penetration rates can start to cause instability on feeder lines, substations or even entire regions.
This used to be a hypothetical problem, but it isn’t any longer, Barrera noted. Some neighborhoods in incentive-rich states like California and New Jersey are seeing penetration rates of 10 percent, 15 percent or even 20 percent or more. At those levels, passing clouds can be more than a nuisance: they can shut off an invisible source of power to the grid, causing frequency and voltage destabilization, and, eventually, power outages.
Utilities don’t know where solar panels are, and can’t control them -- though work is underway to make solar inverters responsive to grid commands. In the meantime, buildings themselves have the ability to shape their own solar output, especially if they have batteries or fuel cells to back them up and the control systems to manage it all. That's what the Aperture Center is meant to demonstrate, Barrera said -- but in the future, the same concepts could be applied to multiple buildings in a neighborhood, or across a city, he said.
NEDO’s next step for the project is to test out solar smoothing, peak shaving and other such operations, Barrera said. While the entire building and environs can run on its own power indefinitely, that would require more use of the natural gas-fired backup power system. The point is not to run on its own as an island -- though it can do that if the utility needs it -- but rather to make solar’s impact on the grid a benefit, rather than a problem, for the utility.
Governments and industry are pouring billions of dollars into research on this front. In the United States, the Department of Energy’s SEGIS (solar energy grid integration systems) program ties Sandia Labs with utilities including PNM, Duke Energy and San Diego Gas & Electric, and companies like Petra Solar and Princeton Power on testing various combinations of smart meters, solar power controls, energy storage systems, customer interfaces and variable pricing schemes. Energy storage companies like A123, Xtreme Power, SAIC and others are backing up wind and solar power for power smoothing and load-shifting.
As for Japan, it is scrambling to deploy smart grid and renewable power en masse to cope with the Fukushima nuclear reactor disaster, which crippled the island nation’s nuclear power production. At the same time, it is seeking foreign markets for its technology -- the NEDO consortium is one of several partnerships pushing Japanese technology to market, including others in the U.S., such as Hitachi’s lead role in a DOE-funded smart grid demonstration in Hawaii.
The list of particular project roles assigned to the nine-company Japanese consortium provides further detail on where these competitors to General Electric, Siemens, Schneider Electric, ABB et al. are staking their claims. According to Barrera, Toshiba is doing the upstream energy management system, Sharp is providing the solar panels, Fuji Electric builds the fuel cells, Tokyo Gas built the cogeneration plant, Mitsubishi Heavy provided the gas-fired power generator, and Furukawa provides both the advanced lead-acid batteries that back up the solar array and the management and operations software for it.