Tucson Tech: New phase of UA Tech Park’s Solar Zone to explore key solar needs
Making solar work better with the power grid is the focus of the second phase of the Solar Zone at the UA Tech Park.
The UA Tech Park is seeking projects for the second phase of the Solar Zone, a solar testing and demonstration site located on the northwest side of the sprawling tech park on South Rita Road.
The UA is earmarking the new area for testing of solar-related technologies involving energy storage, grid management and optimization, microgrids and embedded solar materials.
Because of the intermittent output of solar energy systems — which don’t generate power when the sun doesn’t shine — new storage and grid-management technologies are seen as critical to future adoption.
“We will entertain projects that come up with novel, new ways to generate and distribute solar energy, but our primary focus is in the area of things like energy storage, because that’s a critical component of making these systems more efficient and effective,” said Bruce Wright, associate vice president for Tech Parks Arizona.
At about 10 acres, the new Solar Zone area is small compared with the 225-acre first phase of the Solar Zone, which has served mainly to demonstrate utility-scale solar generation technologies.
The second-phase acreage has actually had its first and biggest project in the ground since last year.
Last June, E.On North America completed the Iron Horse Energy Storage and Solar Project, a 10-megawatt capacity lithium-ion battery-storage facility and an accompanying 2-megawatt photovoltaic array on the new, phase-two area.
Most of the newly opened area will be devoted to five to seven projects using about one acre each, which could include some utility-scale projects, Wright said.
The remaining acreage will host projects involving testing of smaller single-systems, he said, adding that the site is expected to be available by summer after additional fencing and road work is completed.
“They’re not going to be the multimegawatt projects that we’ve done previously,” Wright said.
And while the phase-one projects are based on 20-year ground leases and 20-year power purchase agreements with Solar Zone partner Tucson Electric Power, each of the new projects will last one to five years before making way for new testing tenants.
“We want to turn over the projects and see what’s the latest and greatest,” Wright said.
The second-phase Solar Zone development is being headed by Dick Powell, retired UA optical scientist and former UA vice president of research.
Powell said utilities are eager to find more efficient ways to store solar energy, to make it useful when the sun isn’t shining.
“They’re very happy to put more solar energy on the ground, but they can’t handle the intermittency” of solar generation, Powell said.
Besides advanced batteries, storage technologies that could potentially be tested at the Solar Zone include mechanical systems using compressed air, flywheels and supercapacitors, electrical devices that store energy, Powell said.
Touted by the UA as the biggest solar demonstration site of its kind, the Solar Zone so far consists of nine utility-scale projects on about 225 acres, with various photovoltaic technologies capable of generating 25 megawatts of power that is fed to TEP — nearly twice the daily electrical consumption of the Tech Park and enough to power the homes of more than 4,600 TEP customers for a year.
The project has successfully tested numerous new technologies and is still pumping power to TEP’s grid.
Most of the planned phase-one projects were built, with a few exceptions, and some were altered midstream.
A 5MW thermal solar installation planned early on by a now-defunct company was replaced by other installations.
The former Cogenra Solar, now Sunpower, replaced an inefficient concentrating photovoltaic system using parabolic trough mirrors with a conventional panel system; another test tenant switched to panels with new, more efficient PV cells in mid-installation, Wright said.
“For awhile there, it was very dynamic,” he said.
While most of the existing installations use various types of standard photovoltaic panels, two use concentrating technology designed to increase efficiency by focusing sunlight on solar cells.