Read the following news and try to guess what ideas they have in common and what problems they deal with.

A 13th Century village church is aiming to install solar panels as part of an environmentally friendly fund-raising scheme. Parish officials hope the panels will produce more than enough power to light St Mary's in Lidgate, Suffolk. They plan to sell the excess electricity back to the National Grid. St Mary's is thought to be one of the first churches in the country to try to generate power and extra money in such a fashion. Church warden Michael McEvoy said the scheme, which will cost £12,000, will not spoil the church's architecture. Library of the Free University, Berlin Berlin's Free University has made a self-assured mark with its new library designed by Britain's most famous architect Lord Norman Foster. The new FU humanities library has been nicknamed "The Berlin Brain". And true to its name, the building's curved galleries and stairways actually resemble the winding convolutions of a brain. The fascinating building which opened in September 2005 now unites the 700,000 books that were previously housed in 11 different libraries. From the outside the building resembles a scaled, spherical igloo, while the inside offers an airy, inspiring atmosphere for concentrated study. From the inside an inner membrane of glass fibre gives the impression of looking through a soft-focus lens at the outer bubble-like enclosure of steel, glass and aluminium. "The Brain" is also ecologically friendly: computer regulated vents and a heating system that utilizes the heat-reflecting elements of the structure enable natural ventilation and heating almost all year round. Cost of solar power could fall 40% by2015 Technological advances are driving down photovoltaic panel prices by as much as 10% each year. The cost of photovoltaic panels could fall around 40% in the next five to six years, according to Dutch sustainable energy provider Econcern. The company claimed that system prices are decreasing by 7% to 10% a year as a result of technological innovation and increased production capacity. The development of solar power in the Middle East looks set to exceed growth of solar power globally.Solar energy will be one of the most important sources of energy within 10 years. Medieval architecture inspires zero-carbon home Innovative energy-efficient home based on historic technique of arched overlapping thin clay bricks will star in TV's Grand Designs The four-bedroom Crossway house in Staplehurst uses a large vault constructed out of clay tiles spanning 20m to create a structure with a low embodied energy and high thermal mass. The basic design is adapted from a historic Mediterranean technique called “timbrel vaulting”, which uses thin bricks to create lightweight and durable buildings. Any necessary heating comes from solar energy through the UK's first example of a combination photovoltaic and thermal heating system. While more expensive than some conventional homes, the designers of Crossway believe that its design and technology could ultimately be a prototype for cheaper energy-efficient homes. The building demonstrates how contemporary design can celebrate local materials and integrate new technologies to produce a highly sustainable building that sits lightly on the Earth.