CEDAR RAPIDS — Public interest continues to grow for an effort to incentivize private solar development through volume purchasing prices.James Hodina, environmental services manager with Linn County Public Health, said a total of 34 area residents had contracted for a combined 232 kilowatts of solar power as of Aug. 31 through the Solarize Cedar Rapids and Linn County program.That puts the program — which reached the first goal in July — beyond the second tier of 150 kW and near the third goal of 250 kW.“We’re quickly approaching our next tier,” Hodina said.