May 6 (Reuters) - A sharp rise in electricity demand from data centers is poised to strain U.S. power markets, with consumption more than doubling by 2027 from the end of 2025 as capacity growth accelerates, Goldman Sachs GS.N said in a note on Tuesday.

• Goldman says it expects U.S. data center power demand to grow from about 31 gigawatts (GW) in 2025 to 41 GW in 2026 and 66 GW by 2027, lifting data centers' share of total U.S. electricity demand to around 8.5%.

• This jump in electricity consumption reflects a much faster expansion in installed data center capacity. Goldman expects total U.S. data center capacity will more than double to about 95 GW by the end of 2027 from levels at the end of 2025, even after allowing for delays and cancellations.

• Goldman said the surge in power demand from data centers would incrementally tighten U.S. power markets, many of which are already strained, increasing the risk of higher power prices and reliability challenges.

• The strain is expected to be most acute for regional transmission organizations like PJM in the Mid-Atlantic and MISO in the Midwest and Northwest, where limited scheduled generation capacity could struggle to keep pace with data center growth.

• By contrast, regions including Texas and parts of the U.S. Southeast are likely to see only marginal tightening, reinforcing a regional divergence in U.S. electricity markets.

• Goldman added that the outlook creates two-sided risks for power prices and it urged market participants to hedge against upside risks in tighter regions and downside risks where supply growth may temporarily outpace load.