Drought and heat are driving up power prices for some Montanans Drought and heat are driving up power prices for some Montanans and last updated 2021-07-06 20:15:41-04 HELENA â Drought and high temperatures this summer in the West likely will be bringing yet another discomfort for many Montanans, although not right away: Higher electricity prices. The drought and unusually hot weather have dropped hydroelectric reservoirs to historic lows in California and other parts of the West, crimping supply and increasing demand. Regional power prices are both volatile and spiking. That means Montanaâs largest electric utility, NorthWestern Energy, will be paying millions more than expected to acquire enough power to serve its 380,000 Montana customers, company officials told MTN News.