Two major distributed power technology companies have been boasting about their installation successes in the last couple of weeks – both quoting big numbers.

Of course small-scale distributed generation projects have to be deployed in large numbers to make a meaningful contribution to total generation capacity, and to play significant parts in programmes to raise overall efficiency and reduce emissions.

Over a thousand gas engines manufactured by GE Jenbacher have been installed, in CHP and on-site power projects at industrial sites in Pakistan, since the late 1990s.
Karachi CHP
Engines number 1,000 and 1,001 are each 3.3 MW machines being installed to supply heat, cooling and power to textile mills in Karachi. According to GE, Jenbacher engines with a total generating capacity of around 870 MW now supply energy to Pakistan’s textile industry. Across the country, Jenbacher engines generate nearly 1.5 GW of electricity to power some of the country’s major industries, including the chemicals and manufacturing sectors. That’s a lot of power.

Industrialists in Pakistan must view GE Jenbacher engines very positively – the country has one of the largest concentrations of such engines in the world.

Meanwhile, the Capstone Turbine Corporation reports that 471 CHP systems incorporating its microturbines have been installed in the US to date, in a range of applications from city hospitals to remote shale gas drilling sites.

These CHP schemes avoid the emission of over three million tonnes of carbon dioxide to the atmosphere, compared to more conventional energy sources, according to the US Environmental Protection Agency CHP Partnership. Indeed the Partnership has awarded an emissions reduction certificate to Capstone to recognise this role – it quotes nearly 300,000 tonnes of carbon dioxide avoided by Capstone CHP schemes during 2013 alone.

A thousand on-site engine-generators in Pakistan and towards 500 microturbine-based CHP schemes in the US represent very different parts of the global decentralized energy industry. Many of the schemes in Pakistan will have been installed primarily to improve the reliability of power supplies to the host company, and a good proportion of the US microturbine installations are in remote locations where the utility grid power was not a viable option.

But many other Capstone schemes were installed, European-style, in buildings to cut energy costs and emissions.

The UK has nearly two thousand CHP schemes in total, three-quarters of these under 1 MW in size, scattered across the country. That’s what decentralized energy is about – large numbers of small and medium-scale generation schemes each supplying energy locally to its host organisation or town – but also, collectively, adding up to a significant part of the whole energy generation picture.