Like death and taxes, cold winters in New England are a certainty. Equally as sure is that meeting that heavy demand for electricity, particularly when the weather is extra brutal, is a continuing challenge.

"Our biggest concern is really the issue of the winter energy constraint that we have as the result of insufficient pipeline infrastructure into the region," said Gordon van Welie, CEO of ISO New England, the independent system operator, not-for-profit corporation responsible for keeping electricity flowing across six states.

"The trajectory that we're on is alarming with regard to the reliability of the system," he said of a recent analysis.

Speaking at the 2018 EIA Energy Conference, van Welie said a key issue is that "when it gets really cold, the pipelines can no longer serve gas generation. We switch to burning non-gas fuels," including coal, oil and nuclear. But there's a catch.

"Those resources are the same resources that are most becoming stressed in our markets because they're gradually being pushed out of the markets" by a combination of low natural gas prices and more renewables.

"Our big issue here is how do we find a path forward to address this issue that we've identified and labeled as 'fuel security,' but it really is a winter energy constraint," said van Welie.

There are no easy answers, but he said coordinating facility retirements with the entry of replacement resources, such as offshore wind and a hydro project that's three to four years away, would help.

But for now, van Welie's assessment was blunt: "We're heading towards a riskier fuel security profile."