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New Zealand's large and fast-growing forest plantations are ideally suited for the development of power generation fuelled by forest waste, say visiting experts from Europe.
Dr Arto Timperi from Finland and Lucas Schirnhofer from Austria were in Taupo last week to outline the potential of biomass as an energy source in the country.
They are pioneers in the recovery of wood waste and the development of technologies to convert biomass into heat and electricity.
Dr Timperi, a world expert on forest machinery and energy technology, said about 25 per cent of Finland's energy production came from biomass, of which the bulk was the burning of forest waste.
"In the past 10 years there has been a significant increase."
Dr Timperi said such use of biomass was spreading throughout Europe, including Austria, Germany, France, Spain and Britain.
In Europe all the available tree fibre was bundled up and burned in a controlled environment using filters to remove pollutants.
"The air cleaning technology is very good ... This is a clean, efficient method and the European experience shows it can become a sustainable long-term energy source for the benefit of both the industry and consumers."
Dr Timperi said it was a renewable and carbon-neutral form of energy production, as forest waste would decay anyway, releasing carbon, but replacement trees absorbed carbon back from the atmosphere as they grew. He said New Zealand could easily develop biomass energy systems, especially given that our plantation forests grew much faster than in Finland, due to easier conditions, which increased production to keep the power plants fed.
Dr Timperi said in Finland it had also been found the removal of forest debris was good for the soil.
If left to rot, there was a problem with too much nutrient, which prompted grass growth that swamped seedlings.
He said in Finland the forest waste was gathered, bound up into about 3m-long bundles and delivered to power plants by road or rail.
Tree stumps and root wood were also harvested.
He estimated it cost about $24 to produce each bundle, and although most were transported by roads it was still a profitable energy source.
Dr Timperi cautioned that biomass energy alone was no silver bullet and countries needed to consider a range of renewable options, such as solar and wind power, for their future needs.
He also noted that if all fossil fuels were replaced with nuclear power, the world supply of uranium would run out in three to four years.
Mr Schirnhofer, a senior manager in an Austrian company that led the European market in biomass combustion applications, said there was huge potential for New Zealand to follow suit.
Biomass energy was already used in many European towns to heat large utilities such as schools, hospitals and government buildings, he said.
Where they were located close together, bio-generation could provide electricity as well.
Mr Schirnhofer said the biomass included not just forest waste, but wood residues gathered from farms, sawdust and wood chips.
There could be a problem with emissions of nitrogen dioxide but that was able to be countered, he said.
The New Zealand Clean Energy Centre, which hosted the visiting experts, hopes to foster a wood fuel industry that could be worth more than $150 million a year.
Chief executive Rob McEwen said the lucrative energy source was currently just decaying on forest floors.
"The tops and branches of harvested trees, which are currently unused, can be turned into a valuable energy resource."
The centre was helping Rotorua-based Wastepro Solutions to bring European bundler technology to New Zealand. And in Morrinsville, a cluster of industrial sites was considering sharing a biomass energy plant.
PROCESS
* Bundler picks up treetops and branches left after timber harvested.
* Compacts and bundles them into log-length bales for transportation.
* Bundles chipped and used as boiler fuel for producing heat and electricity.