New England’s electric grid operator says a lack of pipelines is driving the price up for natural gas, and hiked wholesale electricity prices in the region by 55 percent last year.

ISO-New England said Tuesday that the average price of wholesale electric energy rose to $56.06 per megawatt hour, up from a historic low of $36.09 in 2012. …

But ISO said limited pipeline capacity into New England has made it difficult for some natural-gas-fired generators to get fuel, pushing up prices.