HCNG: An alternative to coal and oil?

Saturday, February 24, 2007

A small Western Australia-based company, Eden Energy, is working on a project to convert most of India's public buses to run on a cleaner type of gas that will reduce smog in packed Indian cities. Eden Energy owns the patent for a fuel known as Hythane, or HCNG, a compressed mixture of hydrogen and compressed natural gas.

Scientists discovered that adding hydrogen to natural gas makes it burn more cleanly, reducing its emission of pollutants (notably reducing smog-causing nitrous oxide emissions by around 50%). Hydrogen combines with oxygen when burnt, creating water vapour (and not CO2).

In December, Eden signed a contract to work with Chennai-based Indian bus manufacturer Ashok Leyland to modify Indian buses built to run on natural gas to use HCNG so that they will have much lower CO2 emissions. Ashok Leyland currently manufactures around 80,000 vehicles per year, including 11,000-14,000 buses. It produces the majority of all metropolitan transport buses in India, carrying some 60 million passengers per day.

New buses are to be built with recalibrated engines tuned for use with HCNG. The recalibrated engines will be installed for testing and demonstration purposes throughout 2007 in Delhi, Mumbai, Ahmedabad and Kanpur.

Last October, the Indian government announced a five-year program to expand the distribution of compressed natural gas (CNG) to cover 46 cities and increase available CNG from 5 million to 25 million tonnes. The expansion plan would enable CNG to be supplied for use in up to 60% of all motor vehicles in India.

Although natural gas (methane) is a fossil fuel, it can also be extracted from sewage, animal waste and decaying plant matter sourced from agricultural by-products, biodegradable garbage and food waste.

Because agricultural waste products and sewage are constantly being produced, methane derived from them is categorised as a renewable energy resource, even though burning methane releases CO2 — though burning CNG emits a third less CO2 than burning gasoline or diesel.

Capturing and burning methane from sewage and food waste is better than letting it be released into the atmosphere, since methane is a greenhouse gas that traps heat in the Earth's atmosphere at a rate 21 times greater than CO2.

In a serendipitous coincidence, HCNG presents an exciting possible link between "green" automobiles and wind energy.

One of the main problems with large wind farms is that in high wind, they can actually generate too much electricity and therefore overload the electricity supply grid. Creating hydrogen from water by electrolysis uses enormous amounts of electricity, and could be used to "soak up" surplus electricity from wind farms during wind energy production peaks, while at the same time storing that energy in a widely usable form — hydrogen — to be blended with methane.

Hydrogen could also be made from biomass-sourced methane, by heating methane in combination with water.

On its own, hydrogen is not an immensely practical fuel, requiring sophisticated and expensive piping and/or storage. But HCNG represents a highly practical use for hydrogen, given that its handling properties are virtually identical to those of regular CNG.

HCNG might also be developed for use in gas-fired power stations, providing necessary backup to wind farms in periods of reduced breezes, as well as providing a lower-emission alternative to coal-fired power stations for baseload and peak power generation.

If run solely on biomass-produced methane (rather than natural gas), gas-fired power stations would be carbon neutral. This is because burning bio-methane simply returns to the atmosphere the CO2 extracted from it by plants (and ingested by animals and humans when they eat plant foods), but does not introduce "new" carbon as does the burning of fossil fuels.

Infrastructure that uses gas for generating electricity, running engines and for cooking and heating can be run on bio-methane and, it would seem, the cleaner HCNG blend. Gas-fired power stations, cars and buses should thus be encouraged as part of the solution to global warming and climate change.

Given the severity of climate change, and the urgency with which CO2 emissions must be reduced, research into (and production of) compressed air, petrol-electric hybrid, biodiesel and HCNG engines should be heavily subsidised by the federal government.

HCNG is a cleaner fuel than petrol or diesel. Zero emission cars should be developed but in the meantime greener fuels like HCNG should be widely utilised.

The technological breakthrough made by scientists working for Eden Energy, however, is not available to be used without paying Eden's owners royalties on the company's HCNG patent.

Like AIDS anti-retrovirals, the patents for technologies that can be used to combat climate change should be socially owned, not private property.

Emerging green energy and engine companies are forced to make maximum profits and expand their market share, rather than develop the products with a view to providing affordable, mainstream access to them. The competitive nature of capitalism stunts the integration of clean technologies into existing production capacity.

Capitalist economic relations dictate that green technologies such as low- or zero-emission engines must find their legs as corporations, compete with existing fuel guzzling auto producers (a David versus Goliath battle), and make profits upon profits, for years on end, until they are finally in a position to crush their competitors and become the new dominant technology producers.

Humanity does not have time for this ridiculous slow dance between emerging innovations and satisfaction of the profit drive of the massive intertwined oil, auto and banking monopolies.