By Mark Samuelson

Denver Post Real Estate

Westminster communications engineer John Avenson looks so much like Tom Hanks that during assignments in Asia , people would routinely stop him in airports asking for autographs. His house, open 10-4 today, is a dead-ringer, too…for one built in 1980 under the auspices of the Solar Energy Research Institute. But Avenson has done things with this house that SERI engineers could scarcely have imagined then.

Avenson lives in an area north of Wadsworth Bypass on W. 100^th that was among 12 featured by SERI in a passive solar home tour. At a time when gas was a buck-a-gallon and nobody thought much about global warming, around 100,000 Denverites turned out to see those new houses.

The neighborhood’s builder, Nedlaw Construction, created its SERI design from a typical tract model it was selling by the dozens in blocks around Avenson’s house. The one next door, about the same size, g et s mid-winter energy bills of $200-$300/month…but Avenson, believe it or not, paid XCEL just $17 last February for gas, $10/$15 for power.

During summer, when neighbors are shelling out big bucks to run air conditioners, XCEL actually pays $5 or $10/month back to Avenson, for the surplus juice his 4.76 kW of rooftop solar cells send back to the grid after running all of his lights, swamp cooler and computers.

The photovoltaic cells were too expensive to be included in the 1980s SERI home…but last year it cost Avenson only $14,000 to add them, after rebates from XCEL and the feds.

That’s just the latest of the modifications he’s made over 25 years. The first thing one notices inside is a soft, woman’s voice in a monotone say “Closing the solar blinds now.” That would be REX, Avenson’s computer, which, like HAL in 2001, A Space Odyssey, tracks all of the Boolean functions he’s programmed to monitor the passive solar system, turns on a fan as somebody closes a door or a cloud passes over the sun, and then reports back.

When Avenson first added the system, he named the computer “Computer!”…but that made for problems while he was watching sci-fi movies in his downstairs theater. In one cyber-thriller, as an actor shouted, “Computer! Turn everything off!”, the system did just that. He renamed it REX…hard consonants on both ends, not very feminine.

Avenson also shows off the original storage box of 2-inch river rock under the fireplace that SERI designed to store passive heat, and see displays of new lighting products and other gadgets. Avenson, who lives alone, has signs all over his fixtures and cabinets pointing up their energy performance.