Tesla TSLA may be heading into a much heavier spending phase than expected as it moves forward with its new Terafab chip project, with Barclays suggesting the price tag could get very large, very quickly.

The firm said Tesla’s previously guided $20 billion in capex now looks far too conservative. Even its own bull-case estimate of $50 billion+ may be dramatically low, according to analyst Dan Levy, who noted the total investment could end up several multiples higher. That said, this won’t happen all at once. Barclays expects the buildout to unfold in phases as Tesla gradually works toward an ambitious 1 terawatt compute goal. And importantly, Tesla likely won’t be going it alone, with SpaceX and xAI expected to chip in financially following their recent tie-up.

The Terafab plan, revealed by Elon Musk over the weekend, is all about gaining tighter control over chip supply as AI demand ramps. Right now, Tesla still depends on players like Taiwan Semiconductor Manufacturing and Samsung, but Musk clearly wants to reduce that reliance. The project will start with a smaller facility focused on design and testing before potentially scaling into full production.