Clearway Expands US Battery Fleet With 490-MW Tesla Megapack Order

• Clearway Energy orders 490 MW/1,356 MWh of Tesla Megapacks, boosting its US battery portfolio past 1 GW and underscoring the rapid mainstreaming of four-hour grid storage.

Clearway Energy Inc has locked in another big tranche of grid batteries, signing purchase contracts for 490 MW/1,356 MWh of Tesla Megapack 2 XL units that will be deployed across multiple utility-scale projects in the United States. The order—enough storage to power roughly one million homes for an hour—raises Clearway’s committed Megapack fleet to about 1 GW, supplementing the 520 MW/1,680 MWh already in operation or under construction.

Tesla will assemble the new packs at its Lathrop, California “Megafactory,” the 40 GWh-per-year facility that can turn out as many as 10,000 Megapacks annually. The containerised batteries arrive pre-wired with inverters and thermal management, allowing site crews to crane them into place and connect to medium-voltage gear in weeks rather than months.

Clearway says the storage blocks will support “grid-enhancing services” such as frequency regulation, peak-shaving and congestion relief—tasks that have become more valuable as record volumes of solar and wind crowd into regional transmission systems. Revenue will be stacked from capacity payments, ancillary-service markets and energy-arbitrage trades, insulating project cash flows from wholesale-price volatility.

The order comes on the heels of Clearway’s March financial close on the Honeycomb portfolio in Utah, a quartet of 80-MW Megapack plants totalling 320 MW/1,280 MWh that will supply dispatchable power to PacifiCorp under a 20-year tolling agreement. Company executives say the latest contracts benefit from the same lessons in logistics, software integration and financing structure—key to trimming costs as battery chemistries shift toward lithium-iron-phosphate (LFP) cells with longer life cycles.

While Clearway has not disclosed a delivery schedule, industry analysts expect most of the units to ship in 2026, tapping the expanded production run at Lathrop and taking advantage of the Inflation Reduction Act’s investment tax credits for stand-alone storage. At 490 MW, the order ranks among the largest single US procurements to date, signalling that competitive renewables developers are now treating four-hour batteries as standard kit rather than pilot technology.

Clearway’s storage pipeline now exceeds 3 GWh nationwide, with projects in California, Arizona and the Mid-Atlantic poised to follow. As chief operating officer Valerie Wooley put it in a statement, “Battery capacity is the linchpin that turns intermittent resources into firm, reliable power—and we’re investing at gigawatt scale to make that happen.”