A comprehensive outline of a new approach in integrated gasification of biomass residues including the material flow management in urban areas being targeted on the generation of electricity and district heating is presented. The feedstock is derived from civilian material by fully automated collection, sorting and separation. Thereby an outward transfer of inerts is executed, such as minerals, metals, glass and electronic scrap as well as sorted plastics being object to recycling. Finally a ligno cellulosic and a non-lignocellulosic fraction are gained. The for mer one is suitable for thermochemical conversion, the latter one for biological conversion into fuel gases which subsequently are oxidised completely at low air excess in a horizontally arranged cyclone combustion chamber. The heat recovered from the flue gases in the utility boiler is used to generate steam scooping in the supply of electricity and district heating. The basic design is scaled to an overall thermal capacity of 2-5 MW. This type is most capable of utilising renewable energy by converting the organic fractions of civilian material flows. The power plant is based on a reliable technology representing an on-site integrated biomass gasification combined cycle system including peripheral units specified for the treatment of complementary materials.

This paper analyses the potential to optimize high temperature fluid back-up systems for concentrating solar power (CSP) plants by investigating the cost impact of component capacity and the impact of using multiple fuels on annual generation. Until now back-up heaters have been limited to 20MW(th) capacity but larger units have been realised in other industries. Installing larger units yields economy-of-scale benefits through improved manufacturing, optimised transport, and minimized on-site installation work. Halving the number of back-up boilers can yield cost reduction of 23% while minimizing plant complexity and on-site construction risk. However, to achieve these benefits it is important to adapt the back-up heaters to the plant's requirements (load change, capacity, minimum load, etc.) and design for manufacture, transport and assembly.Despite the fact that biomass availability is decreasing with increasing direct normal irradiance (DNI), some biomass is available in areas suitable for CSP plants. The use of these biomass resources is beneficial to maximise annual renewable energy generation, substitute natural gas, and use locally/seasonally available biomass resources that may not be used otherwise. Even small biomass quantities of only 50,000 t/a can increase the capacity factor of a 50MW(e) parabolic trough plant with 7h thermal energy storage from 40 to 49%. This is a valuable increase and such a concept is suitable for new plants and retrofit applications. However, similar to the capacity optimisation of back-up heaters, various design criteria have to be considered to ensure a successful project.

In recent times the interest in solar tower power plants is increasing with various plants being built in the last years and currently under construction, e.g. Ivanpah and Crescent Dunes in the US and Khi Solar One in South Africa. The higher cycle efficiency leads to lower levelised cost of electricity. However, further cost reductions are required and this paper compares a novel and patented solar tower structure with a conventional concrete tower. The novel solar tower design is cable-stayed which has the benefit that the cables absorb a large part of the wind and buckling loads. A tower that has to cope with fewer wind and buckling forces can have a significantly smaller diameter than a concrete tower, which enables workshop manufacture, sea and road transport, and rapid on-site installation. The case study provided in this paper finds that the tower area affected by wind can be reduced by up to 45%, installation time shortened by up to 66%, and tower cost by 20-40%. The novel design allows the construction and transport of the solar tower in few large modules, which are pre-manufactured including piping, cables, platform, ladders etc. The few modules can be assembled and installed rapidly not only lowering plant cost and construction time but also project risk.