With ratepayer subsidies provided through utilities, farmers are replacing their polluting diesel pumps with electric engines. The programs have cut particulate matter (PM) and nitrogen oxides (NOx) in the Central and San Joaquin valleys after a year and a half of operation. Electrifying irrigation pumps "sharply reduces NOx emissions and particulate matter," said Jerry Martin, California Air Resources Board spokesperson. Martin explained that the air board tried for a number of years to move large numbers of growers to electric pumps, but higher electricity prices and lower diesel fuel costs stalled progress. However, the swap-out largely became a "no brainer" once Pacific Gas & Electric offered 10-year rate discounts and subsidies for line extensions to the pumps, he said. "The incentive program has worked really well," agreed Karen Mills, attorney with the California Farm Bureau. About 15 months ago, PG&E and Southern California Edison began offering farmers electricity rate discounts and financial assistance with grid hookups to new pumps if they agreed to switch to electric engines. Most of the growers with polluting pumps that are 50 horsepower or more are in PG&E territory. PG&E is in the process of replacing 1,480 diesel pumps, representing about 200 MW, over the program's two-year life, said Jon Tremayne, PG&E spokesperson. There are an estimated 6,000 pumps in PG&E territory. In total, there are about 8,600 pumps 50 horsepower or greater in the state. About half of those are in the San Joaquin Valley. Martin acknowledged that the power plants supplying energy to the pumps were not emissions-free. But he added there was a net benefit. "It is far easier to control emissions from one stationary source than from thousands" of pumps. Irrigation pumps in the state spew out about 480 tons per year of PM and 10,400 tons of NOx, according to the air board. "Controls are required to reduce PM when electrification is not feasible," said an air board staff member during a November 16 board meeting. Consumer advocates took issue with the subsidies for the line extensions in 2005, after the program was announced, because the tab will be borne by ratepayers outside the agricultural class. Last year, The Utility Reform Network reached a settlement with utilities at the California Public Utilities Commission that caps the total line subsidy at $27.5 million over the program's life. Farmers turn on their pumps to pressurize sprinklers and move water in their fields seasonally. The irrigation pumps are responsible for only 1.5 to 2.5 percent of the PM and NOx pollution in the valley, Martin said. However, the engines run during the warmer weather, when air quality worsens. Air quality concerns, particularly for ozone, resulted in the state and local air districts setting rules requiring that uncontrolled pumps 50 horsepower or greater be cleaned up or replaced. The state air resources board's regulations strive to reduce NOx emissions by 5,800 tons per year and PM by 330 tons per year. It has provided funding to growers to retrofit or replace their water pumps under the state Carl Moyer Program, which uses a $4 fee on vehicles to fund alternative and less polluting fuels. Since 1996, about 2,200 uncontrolled diesel pumps have been switched to cleaner diesel, compressed natural gas, or electricity under the Carl Moyer program. - Elizabeth McCarthy