ROCKWOOD , Pennsylvania ( CNN ) -- Four generations of Saylors have worked the family 's dairy farm for nearly a century , but for the past three years , the cows have been doing something besides providing milk : They 've been helping power the place . `` The farm used to get a lot of complaints , '' says farmer Shawn Saylor . `` It used to stink a lot . '' Growing up on the sprawling spread 90 minutes from Pittsburgh , 36-year-old farmer Shawn Saylor developed into a self-described science buff . So it was no surprise that , when faced with rising energy costs , Saylor turned to technology . He tapped into an abundant and easily accessible energy source : manure from about 600 cows . Watch how cow poo powers the farm » . `` It 's a pretty simple process . There 's not really a lot to it , '' Saylor said . `` Manure comes from the cows , and there 's energy left in the manure . '' The process is known as anaerobic digestion , and here 's how it works : . With the help of a mechanical scraper in the barn , manure drops into a 19,000-gallon tank . The slurry then moves into the digester , which is 16 feet deep and 70 feet in diameter . It 's heated there for about 16 days while the bacteria break down the organic matter in order to produce methane gas . That gas is burned in two engine generators to make electricity . See an interactive explaining the process » . Heat created by the generators keeps the digester hot , heats the buildings around the farm and helps provide hot water . The electricity is used to power this farm and a dozen neighboring homes , Saylor said . And there 's still some left over , which he sells back to the grid . Overall , the poo power helps Saylor 's bottom line . `` In savings , there 's $ 200,000 a year , in either extra income from sale of electricity or cost offsets , '' he said . `` So you 're talking about system project costs of over a million dollars to build the system but a payback of five years or less . '' Before he installed the system , the pungent smell from the cows could linger for three to four days , Saylor said . `` The farm used to get a lot of complaints from motorists , which is understandable . It used to stink a lot . '' Now , the digesters reduce 98 percent of all odor , although he admits that if the wind blows , you still `` get a whiff . '' The farm 's leftover solid waste is sold to the community . `` We use it for bedding for the animals , '' according to Saylor . `` A lot of people like to get it for their gardens ... because it does n't smell much . '' Farm-based digesters became popular in the United States during the Arab oil embargo in the 1970s . But the technology did n't catch on , possibly because of the high operational costs and declining energy prices , according to the Department of Agriculture . Although Saylor had been interested in digesters for years , his dream did n't become reality until 2006 . That 's when he received a $ 600,000 grant from Pennsylvania 's Department of Environmental Protection . But Saylor 's work is n't done . He intends to make his farm entirely self-sufficient by using waste vegetable oil to make biodiesel fuel . He said his goal is to waste nothing . `` In a biodiesel system , all the waste products can either be used or fed back into the digester to make more gas , '' he said . `` I 've always looked at new technologies and believed you kind of have to work with that stuff to stay with the future . ''
Dairy farmer says he saves money by converting cow manure to electricity . Remaining waste from 600 cows is used as fertilizer and mulch . Anaerobic digestion became popular in United States in 1970s . He says process also helps cut dairy farm 's odor .