Is Solar the Answer to Decreasing Austin’s Reliance on ERCOT?

La Loma Community Solar Farm in East Austin (photo by Jana Birchum)

As oppressive heat continues to pose a deadly threat to Texans, there is one upside – the sun that comes with it is keeping the lights on. Solar has not only been keeping up with record energy demand this summer, but breaking its own generation records. Austin Energy has been a leader in solar for decades, but as it gets ready to update its 2030 net zero plan, environmental advocates think local solar can go even further.

Solar power makes up almost 23% of AE's total generation mix, with almost 90% of that coming from large scale solar arrays. Most of those are out in West Texas, but 15% comes from solar farms in Pflugerville and Webberville. Because the farms out west are huge, they have the lowest energy prices available in the state – but there are benefits to producing solar locally, too. One is reliability – if Austin can build and store local solar here, we won't be as affected by the next Winter Storm Uri blackouts. Plus, the cost of transmitting power to Central Texas varies depending on the market and is super expensive right now, and a dearth of transmission line infrastructure means that some of the power produced in West Texas can't even make it here due to congestion on the lines. Furthermore, any solar power that AE doesn't generate locally, it has to buy from the Electric Reliability Council of Texas market, so "every electron that's generated in our territory is one less electron we have to go out and buy," says AE's Micah Jasuta.

There are two ways AE customers can invest in solar currently – one is a rebate for the upfront cost of installing your own solar panels, and a subsequent bill discount for producing solar power called the Value of Solar (recently bumped from 6.7 to 9.91 cents per kilowatt-hour). But only wealthy homeowners can afford to invest in solar panel installation and expensive batteries, which is why AE is trying to increase its community solar capacity, so that more of the city can use solar.

Growing Local

AE's current local solar capacity is only enough to power about 1% of Austin, and it comes from three arrays – one on the blue parking garage roof at the airport, one on the Palmer Events Center, and the La Loma solar farm northeast of Springdale Road and Airport Boulevard. Half of that power is reserved for Customer Assistance Program customers, who get a discounted rate on their electric bill (about $2), and the other half goes to anyone who wants to subscribe at a premium (~$14) – although all of those slots are currently full.

Instead of building more arrays, AE aims to put solar panels on existing rooftops – called customer-sited solar. This is beneficial to the home or business that has the panels – if they also have a battery, they're more resilient in the event of a blackout – and it's also better for Austin environmentally. "When you put solar on an area that has already been developed, or even covering a parking lot, you're not adding to the human footprint," says Kaiba White of Public Citizen.

In particular, AE is trying to increase that capacity on commercial properties. Histor­ic­ally, "we have just not had quite as much commercial participation as we have residential ... businesses ask for a quicker payback to do solar," says Jasuta. "But we think that now's the time to change that." In October, AE will present a new program to Council called "standard offer," requesting proposals from any commercial property owner to install solar on their property, fully funded by AE, which will then add that power to its local grid. White says, "The idea behind this program is that we can start to use those rooftops, regardless of what the financial situation of the occupant is."

Besides the standard offer program, there are a few incentives to expand solar citywide. The 2017 Solar-Ready ordinance requires new buildings to leave space in the electrical panel and on the rooftop for future solar panels. But White says there should be more incentives for batteries, which are key to decreasing Austin's reliance on the ERCOT grid – without a battery to store energy, it'll all go to ERCOT. For example, White says, there could be a rebate for buying a battery, with the caveat that AE can use it anytime. "I think solutions like that have a lot of merit, and we should move forward with them quickly."

An upcoming process will provide a natural opportunity to push AE's solar goals more aggressively. Last year, in response to the failure to close the coal-burning Fayette Power Project, Council requested updates to AE's Resource Plan, which is its road map to net-zero emissions by 2030. AE will present proposed updates to that plan in February of 2024. Solar currently powers 43,400 homes, and we're about two-thirds of the way to our 2030 goal. Jasuta says AE is on track to meet the plan's current solar goals, "and it's speeding up." Where we're the furthest away is in our customer-­sited goals, which White calls "modest. They're just a reflection of what Austin Energy expects to happen anyway. We've been thinking in tens of megawatts a year. If we can structure something like the standard offer program in the right way, we can be thinking much bigger – we could have thousands."

White says solar can also help move up the timelines for closing AE's gas plants: "I think it's scary for Austin Energy, not having those local sources of generation. And if we can really ramp up deployment of local solar and local batteries, maybe a bit of that fear will start to subside."