(KERO) — State regulators say California is better prepared to avoid last summer's rolling blackouts.

Although they cautioned the power grid of the nation's most populous state is still vulnerable to extreme heatwaves. Officials have acquired an additional 3,500-megawatts of capacity this year. One megawatt is enough to power hundreds of homes.

But, the president of the California Independent Systems Operator says that doesn't guarantee California won't have blackouts this summer. California ISO President Elliot Mainzer says the most significant risk remains extreme heat waves that increase demand for more power.