Storage

There’s a flood (of variable generation) down in Texas helping ERCOT manage demand records

There’s a flood (of variable generation) down in Texas helping ERCOT manage demand records
The Callisto I Energy Center is a 200MW/400MWh battery energy storage system located in central Houston, Texas (courtesy: Jupiter Power)

Jupiter Power’s 400 MWh Callisto I battery energy storage facility in Houston is ready to dispatch to the grid

Demand in the Electricity Reliability Council of Texas (ERCOT) market is higher than ever, but the problems that plagued Texas during record-breaking summer heat last year have so far been abated by the state’s increasingly diverse mix of renewable energy generation and storage.

“We just set a record yesterday,” laughs Joshua Rhodes, a research scientist and professor adjunct at the Univeristy of Texas at Austin. A nearby practicing marching band blares through his end of the cell phone as I interrupt his walk through campus to discuss energy demand in Texas. He doesn’t seem to mind the distraction.

Indeed, according to ERCOT’s grid tracker and local television station KPRC 2, demand hit 85,931 Megawatts (MW) at 4:50 p.m. on Tuesday, August 20, 2024. ERCOT spokesperson Trudi Webster said power demand reached 85,559 MW in the 5 p.m. hour, exceeding the previous record of 85,508 MW set in August of 2023.

In June, ERCOT issued a report predicting August energy demand could hit 78,000 megawatts and admitted a 12% chance of having to resort to rolling blackouts. Despite smashing that demand projection, rolling blackouts have (so far) been avoided. Check out ERCOT’s generation outages over the last six days:

ERCOT generation outages over the last six days (courtesy: ERCOT)

You may recall this time last year when ERCOT repeatedly asked customers to voluntarily conserve electricity as operators aimed to keep demand from exceeding supply. There haven’t been any such calls this summer, and ERCOT’s tracker showed 97,793 MW available at yesterday’s peak, a comfortable distance even on a record-breaking day for demand.

“If you look at the peak yesterday versus almost a year ago to the day, last year’s prices were in the thousands of dollars for multiple hours,” recalls Rhodes. “This time prices were higher, but they weren’t astronomically high, and a lot of that is driven by diversifying Texas’ energy mix. The same sun that heats buildings and makes us crank our air conditioning, driving our peak demand also provides energy for our solar panels. There’s a symbiosis there.”

So demand is high but prices are staying in check and ERCOT is avoiding rolling blackouts? How did Texas turn things around so quickly? Increasing load, and fast.

During a board meeting in Austin on Tuesday, ERCOT CEO Pablo Vegas and other officials credited new energy sources that have been brought online, per television station KVUE. And there’s more coming online in critical areas.

There’s a flood (of variable generation) down in Texas

UT-Austin’s Rhodes says about 8 GW of solar generation has been added to ERCOT’s grid since last summer, including about 5 GW in the first quarter of this year alone, further balancing Texas’ renewable energy mix. Even when the wind isn’t blowing, ERCOT has managed to keep energy prices in check this year.

“Wind and solar work really well together,” he notes. “We deployed a lot of wind when it was cheapest to deploy, then we deployed a lot of solar as it got cheaper.”

And what’s next?

“Now batteries are getting there,” he acknowledges. “We’ve got a lot of variable generation, which is great for storage resources, which is why we’re seeing this third wave of storage.”

Admittedly, ERCOT runs on a lot of natural gas. But it could run on more renewables, if it weren’t for insufficient transmission capacity. Renewable energy curtailment is an unfortunate but necessary side effect of Texas’ connect and manage approach to getting Distributed Energy Resources (DERs) onto the grid quickly. According to a recent report, solar generation can be curtailed in the neighborhood of 20%- a ghastly proposition not only for generators, but for ratepayers spending more to burn natural gas and wasting free sunshine or wind resources.

“The more congested the system is, the less reliable it’s going to be,” explains Rhodes.

And that’s where batteries can really benefit Texas- rather than building new transmission, battery energy storage systems can serve as forms of variable generation to make better use of the surplus of renewable resources already on the market.

Texas has about 8 GW of battery capacity right now, up about 35% from the start of the year, according to ERCOT. The state has been a bastion of BESS development since Winter Storm Uri killed 246 people and ravaged the Texas grid in February of 2021. Since then, ERCOT’s battery capacity has grown by more than 2400%. Rhodes sees no sign of that trend changing.

“Batteries are going to come in as a lower priced option that results in less congestion on the system,” Rhodes predicts. I suppose it makes sense that they’d start cropping up in the expected places…

Jupiter Power commences operations on a big battery in Houston

“The Houston area is often one of the regions with highest electricity prices, indicating there are constraints getting more power into that region, confirms Rhodes.

That makes Jupiter Power’s latest announcement all the more impactful.

The Austin-based energy storage company has achieved commercial operations of 400MWh of dispatchable power to the ERCOT grid from its Callisto I battery energy storage facility in Houston, Texas. This new facility is a product of the market-based improvements in recent years that have made it more competitive to dispatch stored power to the ERCOT grid, says Jupiter Power.

“This project responds to lawmakers’ calls to increase affordable and dispatchable new generation in an area where people need more power,” stated Andy Bowman, the company’s chief executive officer.

The Callisto I Energy Center is a 200 MW/400 MWh battery energy storage system located in central Houston, five miles from the Medical Center and ten miles from the Houston Ship Channel at the site of a former HL&P H.O. Clarke fossil fuel power plant. The site can accommodate an additional 400MW/800MWh of battery energy storage generation, per Jupiter. Callisto I is Jupiter’s ninth project in ERCOT, bringing its total ERCOT fleet to 1,375MWh.

“Jupiter couldn’t be prouder about bringing the Callisto I project online,” said Bowman. “Callisto I is the first energy storage project at this scale in the City of Houston and will help meet Houston’s growing power needs while also increasing resiliency from extreme weather events.”

“It’s the first large-scale, transmission-connected energy storage project in the City of Houston,” noted Jane Stricker, senior vice president of the Greater Houston Partnership and executive director of Houston Energy Transition Initiative (HETI). “This critical project will help address peak power demand and is another great example of our region’s leadership in scaling and deploying impactful solutions for an all the above energy future.”

“It is essential that Texas has a diversified generation portfolio,” added state senator Charles Schwertner, Chairman of the Senate Committee of Business and Commerce. “Batteries play an important role within that portfolio to help address demands in times of need.”