Cement plants have become more automated, integrated and efficient since Henry Kaiser founded the Kaiser Cement Corporation — now known as Hanson Permanente Cement — in 1939 in the hills above Cupertino, California. But the 11 cement plants in California churn out the stuff in largely the same way they have for many decades — an issue that has earned the attention of a Climate Action Team subgroup.

The group, comprised of environmentalists, industry representatives, and state agencies such as the Air Resources Board, is working on plans to implement AB32, passed in 2006 to mandate a statewide reduction in greenhouse gas emissions to 1990 levels by 2020, MercuryNews.com reports.

Cement plants are looking at different fuel sources and the Bay Area Air Quality Management District has granted the Hanson plant a permit to increase its use of petroleum coke to heat its kiln from eight tons per hour to 20 tons per hour. Pet coke is a byproduct of petroleum production and is high in sulphur and low in volatile content, according to Wikipedia.

One factor in the new fuel’s sustainability factor is that its source is a refinery in the Bay Area, while the coal the plant uses is transported from states such as Utah, but some say it may not be the best solution.

While its high-heat and low-ash content make pet coke a good fuel for power generation in coal fired boilers, it poses some environmental and technical problems with its combustion. In order to meet current North American emissions standards, some form of sulphur capture is required.

Interim results of an 18-month trial burning a blend of coal and petroleum coke at Drax Power Station in the U.K. in 2006, showed no adverse impact on the local environment, the company said.

Cement manufacturers are also working towards more environmental end products.

US Concrete has said that it’s implementing environmental technologies that will reduce potential carbon dioxide emissions by hundreds of thousands of tonnes annually.