* Carbon capture projects repeatedly delayed
* Seen crucial to clean up fossil fuel power plants
By Gerard Wynn
LONDON, July 21 (Reuters) - A dream climate change cure to turn planet-warming greenhouse gases into useful products from jet fuel to plastics will take years to develop from the lab and pilot projects, a report found on Thursday.
Pilot projects already use carbon dioxide (CO2) to feed plants, for example to boost tomatoes in glasshouses, while laboratories have tested the manufacture of concrete, plastics and oils, but costs are high and projects depend on concentrated streams of CO2.
Scaling up depends on applying the technology to fossil fuel power plants, trapping the greenhouse gas from a diluted mixture of other flue gases.
Converting the trapped CO2 into useful products and minerals would avoid the cost of burying it underground in empty oil wells, as planned under another untested process called carbon capture and storage (CCS).
"At the moment it's a relatively new technology in the shadows of CCS," said Sheffield University's Peter Styring, co-author of the report, "Carbon capture and utilisation in the green economy", commissioned by the UK-based Centre for Low Carbon Futures.
Possible applications centre around chemical conversion of CO2 to make plastics or fuel, or else feeding the gas to algae to make bio-oils, or combining it with minerals to make construction materials.
The report listed pilot projects including the planned manufacture of cement from power plant carbon emissions in Australia, and a synthetic diesel made from CO2 in New Mexico.
German chemicals company Bayer (BAYGn.DE) earlier this year launched a pilot plant to produce plastics using CO2 from a power plant, under the company's "Dream Production" programme.
In algae applications, CO2 is used to boost natural photosynthesis, in cultures which are then squashed to make bio-oils for a range of products including jet fuel, diesel, cosmetics, food, animal feed or soil conditioner.
The trouble is bio-oil costs must be cut ten-fold to be economic, said co-author Hans Reith at the Energy Research Centre of the Netherlands.
Making construction materials by reacting CO2 with minerals found in naturally occurring rocks or in ash from power plants is challenged by the vast amounts of feedstock required.
Practicable applications may be at the local scale, for example trapping CO2 from waste incineration, to feed the gas to algae for the manufacture of diesel to run garbage trucks.
A similar report on the "re-use" of CO2, published by the Global CCS Institute earlier this year found that "most of the emerging reuse technologies still have years of development ahead before they reach the technical maturity required for deployment at commercial scale." ($1 = 0.704 Euros) (Editing by Keiron Henderson)