ExxonMobil announced last month that it is to invest more than US$1 billion in new oil-to-transportation fuels equipment at the company’s refinery in Antwerp, Belgium. The oil major stressed its commitment to producing diesel and other fuels in Antwerp for use throughout northwestern Europe, despite ‘extremely low margins and industry-wide losses in Europe, primarily due to excess refining capacity’. The announcement also mentioned that ExxonMobil had recently completed a 130 MW cogeneration plant at the Antwerp refinery.

Oil refineries exemplify large-scale cogeneration at its resource-efficient best – serving an industry that often has ‘waste’ fuels available for use, and always has large and continuous energy loads to be met.

ExxonMobil says that, through cogeneration, it can generate power more efficiently than many local utilities. The company has interests in over 5 GWe of cogeneration capacity in more than 100 installations at more than 30 locations around the world. The oil major says it has invested more than $1 billion in cogeneration projects in the last decade.

And it’s not just one company. In the last few months the COSPP website has reported on major cogeneration plants being built for Malaysia’s state-owned oil company, Petronas, and Mexico’s Pemex. Siemens and MMC Engineering Services are building a 1200 MWe cogeneration plant to provide nearly 1500 tonnes per hour of process steam to Petronas’ petrochemical complex in Pengerang, Malaysia. Meanwhile, Spain’s Iberdrola Ingenieria is building a new line to carry steam from its 430 MWe Salamanca cogeneration plant, completed a few years ago, to a Pemex refinery in central Mexico.

So, do energy conversion industries other than oil refineries pull a similar trick? The coal seam gas processing industry certainly does, if not with cogeneration then with locally-generated power. Many mines operate in remote locations where an on-site power supply can be essential.

For example, two coal seam processing plants currently under construction in rural Queensland, Australia, are to incorporate on-site power plants, based on GE Jenbacher engines and installed by the Jenbacher distributor in Australia, Clarke Energy. The first project, at the Reedy Creek coal seam facility, is an extension of an existing 30 MW on-site power station with the addition of 10 new 3 MW engines, doubling the plant’s generating capacity. Clarke Energy is also supplying nine engine-based generators to make a 27 MW power plant for the Eurombah gas processing facility. Both plants will be fuelled with locally-extracted coal seam gas until permanent electrical infrastructure can be installed.

Closer to cogeneration is the coal seam gas-fuelled facility supplied by Caterpillar Electric Power for the Shanxi Jincheng Anthracite Coal Mining Company in China. Here, gas is collected from underground coal seams to power four on-site combined-cycle power plants based on Caterpillar engines. To boost efficiency, heat from the engine exhaust systems is recovered to power a steam turbine that generates additional power.

There are plenty of opportunities for energy conversion industries to adopt high-efficiency cogeneration or on-site power supplies. For the former, substantial energy loads, ideally for nearly continuous periods of time, will help a cogeneration plant deliver maximum benefits. The latter on-site supply option is often essential to serve remotely-located plants. In both cases, the ready availability of ‘free’ fuel from the energy conversion process is an additional bonus.

Steve Hodgson   Steve Hodgson
Contributing Editor