A Brief History of Renewable Energy Engineering at Caterpillar
on 08-19-201301:14 PM - last edited on 08-26-201311:09 AM by cboysen
I recently received an invitation by a Caterpillar customer, Luc Turcotte of EBI Energie, and our local Caterpillar dealer salesperson, Regis Drouin of Hewitt Equipment, to visit what was billed as the most advanced landfill-gas-to-energy (LFGTE) facility in North America. With that kind of billing, it was an offer that I couldn’t refuse.
I had visited LFGTE facilities prior to this trip, but nothing quite like what I was about to see at EBI’s facility near Montreal. My colleague, Mike Devine, who has 20 more years in the power business than I do, often reminds me that Caterpillar has been in the renewable energy business even before his tenure—a fact that escapes many consulting engineers and project developers these days. My goal for this trip was to put together a video and technical article for a trade publication that would spell out how new technology can impact the approach on new green energy projects. On the plane ride from Chicago to Montreal, I thought a lot about the history that got us where we are today.
You see, since the 1960s, Caterpillar has been applying engines to run on biogas. Some vintage model G333 to G399s were applied as pump engines in wastewater treatment plants operating on the gases extracted from the wastewater treatment process. It wasn’t until 1985 that Caterpillar adapted a natural gas G3516 generator set for landfill methane fuel. At that time, U.S. government regulations were just being activated that made sanitary landfill construction mandatory. Those regulations helped support a landfill energy program because for the first time, modern landfill construction made it possible for landfill gas wells to efficiently extract ‘nuisance’ methane gases. During this time, the primary goal was to burn off landfill gas in order to protect groundwater and improve the quality of life of surrounding communities. Nobody knew if landfill gases would even work as a renewable fuel in an engine generator, and nobody in the engine business had heard of siloxane or had seen what it could do to the insides of a gas engine. Because of a strong relationship within our heavy equipment division, Caterpillar had partnered with Waste Management to try out a modified 16-cylinder G3516 rated around 800kW on landfill gas. The generator set was packaged into an ISO container so that if the engine failed it could be quickly exchanged, repaired or applied at a different site. Fast forward 28 years, and today Waste Management is applying enough Cat gas generator sets to power half a million U.S. homes.
From 1983 to the early 1990s, more engines were being applied on landfill projects and product development flourished. Caterpillar differentiated itself with stainless steel after-cooler cores, elevated jacket water temperatures, special exhaust valves, seals and bearings that were specifically designed for these applications. In 2005, Caterpillar added four cylinders and nearly doubled the power density of a landfill engine with model G3520C rated for 1600kW at 1200rpm (2000kW at 1500rpm). Doubling power density also doubled the amount of corrosive landfill gases consumed inside the same engine. As many engine manufacturers were focused on the natural gas business in the 1990s, other technology paths sprouted that focused on treating fuel to make it nearly as clean as natural gas versus using a specialized engine design. More sophisticated fuel treatment technologies developed included gas chillers, regenerative adsorption silica gels and activated carbon. This is the technology path Caterpillar followed by acquiring MWM, based in Mannheim, Germany, which today manufactures the Cat CG line of generator sets for operation on both biogas and natural gas.
The investment and sophistication of the engineering that I experienced during my recent visit to EBI Energie in Quebec was even more notable. Be sure to keep your eyes open for our upcoming Power Profile and YouTube video on this project. You can view all of Caterpillar’s Landfill stories on the Gas Power website.
- What is your experience in applying Caterpillar engines versus other engines on landfill gas fuels?
- What new technologies do you think could change the way these projects are being executed?
- Should local governments be playing a stronger role in driving biogas-to-energy programs?