ST. PAUL — Minnesota is looking to grow its share of electricity fueled by the sun and is counting on community solar gardens to help make it happen.

A sweeping state energy law approved this spring demands that utilities generate or procure 1.5 percent of their power from solar sources by 2020 — a big step up from where the state is now. Under that law, Xcel Energy Inc. has until Monday to tell how the giant electricity provider would like to manage the rollout of the developer-driven gardens, which are neighborhood hubs of solar panels used to generate small amounts of power for the utility.

Rather than relying on people forking over thousands for a few glass panels atop their homes or businesses, gardens will allow them to claim a slice of a bigger solar array through subscriptions. While the electricity produced goes into the general power grid, subscribers get breaks on their monthly bills based on their share of the solar energy that’s harnessed.

“Community solar is how we’re going to provide this opportunity for the masses. It is the Model T of solar energy,” said Ken Bradley, chief executive of Minnesota Community Solar, an upstart company already cultivating sites and a subscriber base.

It’s a concept that has taken hold in other states, mostly out West. Xcel is more than a year into a similar program in Colorado. If all goes as planned, the Minnesota gardens will start cropping up next year.

In an interview Friday, Xcel officials previewed Monday’s filing but declined to reveal specific details before it’s formally submitted. The company’s plan is subject to Public Utilities Commission approval and will dictate how soon the projects ramp up.

Deb Sundin, an Xcel director of renewable strategy and planning, said the company would seek to limit the number of new solar megawatts it accepts every few months to make sure the company’s engineering systems can manage the intake and so that gardens that are better developed can get approval more quickly. She said the plan also structures the bill credits available to subscribers. And the company wants assurances that the power produced from the gardens count toward Xcel’s solar power mandate rather than be allowed for sale on the open market to companies looking to achieve similar goals.

The law requires customer subscriptions to be for at least 200 watts of generating capacity and a person or entity can’t own more than a 40 percent interest in a garden. It’s possible someone could buy a stake that produces more power than they consume, allowing them to make money on their investment.

Sundin and Xcel regional vice president Laura McCarten said the program should make it more attractive for people to grab a stake in solar power.

“Obviously there are those who feel they’re more environmental with their energy use are going to be interested in this,” Sundin said. “We are also going to see gardens that are promoted by church groups, cities or counties or maybe schools. There’s going to be multiple motivations for participating.”

The utilities commission has no timetable to act and will seek public comment first. Other investor-owned utilities in Minnesota can develop their own programs but weren’t ordered to like Xcel.

As states try to encourage utilities to reduce reliance on coal and other fossil fuels, they have set mandates attempting to boost use of renewable sources such as hydropower, biomass and wind. Solar remains one of the smallest electricity sources, at 0.11 percent of all electricity produced in the country in 2012, according to the U.S. Energy Information Administration.

Minnesota Republicans resisted the solar mandate, arguing it will drive up electricity rates. Rep. Pat Garofalo, R-Farmington, said the community gardens could be too expensive for most customers to tap into and those with the financial means will reap the rewards.

“Many people will perceive this as free money and free money is always popular. But ultimately someone is going to pick up the tab for this,” Garofalo said. “There are more affordable, more efficient ways to provide renewable energy. We should be giving flexibility to provide that instead of mandating in law a certain power source.”

House Energy Policy Committee Chairwoman Melissa Hortman, DFL-Brooklyn Park, predicted the costs of solar would fall as demand for the commodity rises. Hortman said she doubts utilities would embrace the push for community-derived power if they didn’t face a requirement.

“We wanted to have more people have the ability to become power producers and sell it to the utilities,” Hortman said.