Rep. Seth Berry’s proposed public takeover of Central Maine Power and Emera might seem groundbreaking, but it’s a logical and proven answer to a question facing many American policymakers. If technologies like solar and batteries provide affordable competition to the existing utility – just as cellphones offered an alternative to landline phone companies – then why should governments continue protecting monopoly utility companies that make bad bets, provide poor service and raise prices?

Berry isn’t alone. Policymakers across America are enabling local ownership of energy infrastructure – energy democracy – to reverse decades of (increasingly costly) energy monopoly.

Mainers are victims of an outdated idea. One hundred years ago, state governments gave utility companies monopolies over electricity generation and delivery to lower costs. Protected from competition, these companies grew larger and more powerful. Utility shareholders got richer and customers paid less.

In the last quarter-century, this mutual benefit was strained as many utilities made terrible bets on expensive transmission upgrades, just as customers started using less energy. Many states responded with more oversight. Unfortunately, public oversight hasn’t kept pace with the poor decisions of companies insulated from competition, or with the size of utility companies, which hold more sway over state legislatures as they’ve merged into multi-state, multinational holding companies. More than most states, Maine is bearing the brunt of these bad decisions.

Signs of monopoly failure have popped up across the country. The multi-utility V.C. Summer nuclear power plant project collapsed last year, leaving a $9 billion bill for South Carolina customers. California’s Pacific Gas & Electric recently declared bankruptcy, caught between wildfire threats to their expensive power lines and competition, as thousands of customers have left for community utilities. In Maine, thousands of electricity customers have seen their bills jump by 50 percent or more.

When competitive businesses make mistakes, they pay the price. When monopolies make mistakes, we pay the price.

Building big has become a costly utility habit, because customers increasingly have alternatives – despite the government-provided shield from competition. Californians have added enough solar to their own rooftops to equal two nuclear power plants in the past decade. In the same period, homes and businesses in Massachusetts and New Jersey have built enough solar to power a half-million homes. In three years in Minnesota, residents and businesses have signed up for community solar projects with enough capacity to power a mid-sized city.

Energy entrepreneurs have developed smart thermostats and smart appliances to give customers more control over their energy use. Solar companies package batteries with one in 10 new installations, further reducing a customer’s reliance on their utility company. The Institute for Local Self-Reliance estimates that by 2022, nearly half of all residential energy customers – up to 73 percent in Maine – could produce cheaper electricity with solar panels on their roof combined with a battery pack than they could buy from their utility, assuming electric rates continue to rise. At the same time, electric vehicles and gas furnace alternatives like heat pumps allow customers to use clean electricity instead of oil or fracked gas.

In other words, there’s a conflict between the more democratic and competitive emerging energy system and the dominant model, where governments like Maine’s shield big monopoly companies from competition.

Policymakers everywhere are striking a similar anti-monopoly chord. In light of the multibillion-dollar V.C. Summer nuclear plant debacle, Republican South Carolina state Sen. Tom Davis said, “It is time to break the utility stranglehold and allow energy competition in the residential and corporate sectors.” In response to PG&E’s self-created challenges, the California Public Utilities Commission says it is considering all options, including that “some or all of PG&E be reconstituted as a publicly owned utility or utilities.” Proposed federal energy policies articulate a goal of “ensuring a commercial environment where every businessperson is free from unfair competition and domination by domestic or international monopolies.

Like public roads, it is time to operate the electricity grid as a commons to facilitate competitive enterprise. With lower interest rates and no private shareholders, a public electricity grid promises lower costs. Most important, a public grid helps break the monopoly stranglehold on the electricity system, reducing the political influence of large utility corporations while creating a more level playing field for Maine’s electricity customers to generate their own affordable, clean-energy solutions.