John Brandenburg used to run his oil-fired furnace year-round because it heated water for showers and sinks as well as for the baseboard heaters in his Howard County home.
"We had to run the boiler all summer, and that seemed ludicrous," the Glenelg resident said.
To curb his rising oil bills, Brandenburg installed solar panels for hot water, a move made easier by a county program offering tax credits to homeowners with alternative energy systems.
"I wanted to do it just on principle to try to reduce the carbon footprint, but another rationale was the [financial] incentive," he said.
Brandenburg is among a small but fast-growing group of Howard County homeowners who are taking advantage of government credits and grants to install solar or geothermal heating systems.
In the second year that the county offered the tax breaks, which ended April 1, the number of participants grew from 10 households to 44, said Linda Watts, chief of the county Finance Department's Bureau of Revenue.
"We anticipate more," she said.
Howard's experience mirrors the national picture for solar and geothermal energy, according to statistics from the Solar Energy Industries Association, an industry trade group. Installations of whole-house solar heating systems increased 45 percent from 2006 to 2007, and the addition of solar water heating has more than doubled since 2005.
Other jurisdictions in the Baltimore region report growing interest in their incentive programs. In Harford County, which increased its credit in March, applications rose from two last year to 25 this year, said Anne Gessner, an accountant in the treasury office.
Anne Arundel County, which awarded a credit to one applicant last fiscal year, saw the number of applicants jump to 10 for the new fiscal year, a spokesman said.
Montgomery County launched its program Tuesday, and officials in Baltimore and Prince George's counties say they are considering doing likewise. Baltimore City does not offer such a program.
The number grants - and the dollars distributed - has increased fivefold for the state program that started in 2005 with about $100,000 for 44 projects. A federal program chips in 30 percent of the remainder after local credits are applied.
In Howard, the county provides up to $1,500 in tax credits for a solar system used to heat water and up to $5,000 for a solar or geothermal system that provides all of the energy for the home.
