Hyper-efficiency with Combined Heat and Power systems using bioenergy

Traditional fossil fueled power plants achieve an efficiency of anywhere between 30 and 40%. Their CO2 emissions contribute greatly to global warming. Such power systems stem from an era where power production was heavily centralised and controlled by large single-point utilities.
Now that we are entering the bioenergy future, far more efficient systems are gaining in popularity, especially in Europe. Take 'Combined Heat and Power' (CHP) or 'cogeneration' systems, which recover the large amount of 'waste heat' that gets released during the production of electricity. CHP systems put it to use to heat and cool buildings and to deliver hot water to communities ('district heating'). As such, CHP systems often achieve more than twice the efficiency of their old world counterparts. The spatial and conceptual framework resulting from these systems changes as well: local resources are distributed in a decentralised manner and are controlled by local communities.

So far nothing new. The ideal power system however consists of a CHP system using bioenergy feedstocks. And several European countries - most notably Germany and France - are leading on this front, using locally produced woody biomass, agricultural waste or dedicated biofuel crops (even though several large plants are also sourcing biomass internationally, even from the tropics). This way, CO2 emissions are greatly reduced (compare it to traditional fossil fuel power plants: the fuel has to be transported in, which requires a CO2 intensive logistical chain; during the production of electricity the fossil fuels emit their CO2; and since these plants are not very efficient, a comparably small amount of usable energy is actually produced).

An interesting illustration of sustainable, green power generation based on a CHP system comes from the community of Ottignies-Louvain-La-Neuve, in Belgium. This city is one of the leading partners of the EU sponsored Sustainable Cities network, which pools cities in North-Western Europe that have developed world leading expertise in sustainable urban energy solutions. The town is now building a CHP plant which uses locally produced pure colza (rapeseed) as the prime feedstock. The biofuel is sourced from farmers living within a small perimeter around the plant, in order to reduce transport costs and CO2 emissions. This way, the Ottignies' plant boosts local agriculture. The system will deliver 100% of the elecricity of the community and 70% of its heating and cooling needs:

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The system makes use of the most optimal and rational combination of the existing electricity system and the new power production plant. At night, when less heating is required, the co-generator's capacity is turned down and the buildings use elecritity from the old utility. When the need is greatest, both operate at the same time. In case an excess is produced, it gets fed into the national grid or directly sold to big consumers under a new licencing system that foresees "ad-hoc" buying and selling of electricity.
The Ottignies' plant will reduce the cities' natural gas bill considerably and will same some 290 tonnes of CO2, for which it receives 850 green certificates per year.

More information:
About the European Sustainable Cities network: Sus-Cit.
For the Ottignies plant, see: La Libre Belgique: Ottignies voit la ville en vert or in Dutch, Flemish Information Centre on Agriculture and Horticulture: Ottignies combineert WWK-installatie met koolzaadolie.

Information about CHP and co-generation systems:
The European Association for the Promotion of Cogeneration: COGEN EUROPE
Belgium: Belcogen; Cogen Vlaanderen.
Finland: High cogeneration performance by innovative steam turbine for biomass-fired CHP plant in Iisalmi
CHP Association