Energy-efficient features such as low-flow faucets, R-50 ceiling insulation and airtight windows aren't sexy. But they can save homeowners up to 30 percent in monthly energy costs.

Find out how it's done at Xcel Energy's Energy Efficient Homes on Tour, a selection of 40 newly built Twin Cities homes that incorporate green design, sustainability ideals, and energy-saving products and materials.

The homes cover a range of prices and styles -- from an Inver Grove Heights cottage with eucalyptus flooring to a modern-day green farmhouse in Afton with geothermal heating and cooling. All of the homes have been certified by Energy Star or the Minnesota GreenStar programs.

The event is free. Hours are noon to 6 p.m. Saturdays and Sundays and 4 to 8 p.m. Fridays through April 25.

For tour maps and guides, go to www.mspmag.com/energyhome or Twin Cities Warners' Stellian and Hirshfield's stores.

LYNN UNDERWOOD