Metropolitan Council honchos and others on Tuesday will tour the new solar energy "farm" at Shakopee's Blue Lake Wastewater Treatment Plant — the largest project of its kind in the state.

The $3.6 million farm is expected to produce about 10 percent of the energy now consumed by the plant, and it's the latest solar initiative announcement from the regional planning agency. (Xcel Energy contributed a $2 million grant toward the Shakopee project.)

Last month, Metro Transit announced that it will install solar panels at bus garages in Minneapolis, Bloomington and St. Paul, a light-rail maintenance facility on the Blue Line, and a bus-maintenance facility in St. Paul. The solar panels will produce about half the energy consumed at those sites.

Solar City, a fast-growing installer of rooftop solar systems nationwide, will pay for the installation and equipment. Metro Transit says the rooftop "arrays" will produce 4.7 megawatts of solar power and save about $4 million in energy costs over the next 25 years.

Existing solar panels currently offset energy costs at a light-rail support facility in Minneapolis and at a Park & Ride garage in Brooklyn Park.

Light-rail trains consume 71 percent of Metro Transit's electricity, buses consume 23 percent, and the Northstar commuter rail uses 6 percent. Most (61 percent) of the electricity supplied to Metro Transit comes from fossil fuels and nuclear power, although General Manager Brian Lamb wants "sustainability [to be] at the forefront of everything we do."

Meanwhile, at another transportation hub across town — the Minneapolis-St. Paul International Airport — work is nearly complete on a $25.4 million solar installation on two parking ramps in front of Terminal 1 (Lindbergh).

In 2012, the Metropolitan Airports Commission hired Minneapolis-based GreenMark to explore energy projects at the airport, and the parking lot panels resulted from that effort.

But, don't worry, no parking spots were lost to make way for the panels.

Janet Moore • 612-673-7752 @MooreStrib