ECL's 35-megawatt Santa Clara AI data center is fully leased before it is finished
The developer plans to make most of the site's power itself, from natural gas and hydrogen.
All the space in a new AI data center in Santa Clara has been spoken for before construction is done, its developer ECL said Tuesday. ECL has not said where in Santa Clara the site, called CSC1, is, and data center directories list its exact address as not public.
ECL said three tenants signed up for CSC1, its 35-megawatt site. A megawatt is a million watts; 35 megawatts is roughly what tens of thousands of homes use. ECL did not name the tenants. It said they include AI cloud companies and startups backed by AI research groups, and all will run inference, the work of answering users' requests with already-trained AI models. Tenants move in starting early 2027, and the building should be finished in the second half of 2027.
Making most of its own power
The 35 megawatts is the building's total capacity, and ECL plans to generate most of that power itself, on site. Big data centers often wait years for a utility to connect enough power, and ECL said AI companies in the Bay Area face years-long waits in line for grid hookups. Santa Clara gets its electricity from Silicon Valley Power, the city-owned utility. ECL's FlexGrid design takes up to 5 megawatts from the grid and makes the rest on site, with up to 30 megawatts from natural gas microturbines and fuel cells and up to 5 megawatts from hydrogen fuel cells, backed by batteries, ECL said. The mix can change over time. ECL said that cuts building time to nine to 12 months.
Water
ECL said the servers will be cooled partly by liquid piped directly to the chips. When hydrogen is used, water given off by the fuel cells feeds the cooling system instead of fresh water, ECL said. Hydrogen supplies at most 5 of the 35 megawatts, and ECL did not say how much water the site will use overall.
ECL, which opened a hydrogen-powered AI data center in Mountain View in 2024, said three more Bay Area sites, CSJ1, CSU1 and CSU2, are open to tenant inquiries. It did not say where they are.
Sources: ECL news release via Business Wire, Nov. 3, 2026; Data Center Map listing for CSC-1