After tremendous growth in recent years, China now has 44.7GW of wind-derived power and has surpassed the US (40.18 GW) to be the largest wind turbine owner since the end of 2010. In 2010, around half of the new wind turbines globally were installed in China. Despite the recent growth rates and promises of a bright future, two important issues -the capability of the grid infrastructure and the availability of backup systems -must be critically discussed and tackled in the medium term.The study shows that only a relatively small share of investment goes towards improving and extending the electricity infrastructure which is a precondition for transmitting clean wind energy to the end users. In addition, the backup systems are either geographically too remote from the potential wind power sites or currently financially infeasible. Also, the use of coal-fired plants as the backup system is unavoidable because of the coal-dominated electricity mix. Finally, the introduction of wind power to the coal-dominated energy production system is not problem-free. Frequent ramp ups and downs of coal-fired plants lead to lower energy efficiency and higher emissions, which is likely to compensate some of the emission savings from wind power.The current power system is heavily reliant on independently acting but state-owned energy companies optimizing their part of the system, which is partly incompatible with building a robust system supporting renewable energy technologies. Hence, strategic, top-down co-ordination and incentives to improve the overall electricity infrastructure is recommended.

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In an attempt to manage tin segregation in steel, the formation of intermetallic compounds of tin with niobium, titanium, and aluminium was investigated. T wo series of alloys based on Fe, Sn, and Al with either Nb or T i additions were prepared by arc melting under argon. After cold rolling, the alloys were annealed at 850°C for 96 h. T he microstructures were studied using scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray spectroscopy, and microprobe analysis. T he level of Nb addition was found to aVect the formation of Sn rich compounds. For small Nb additions, no Sn containing compounds were found, whereas the higher Nb alloy exhibited a Fe 2 Nb based L aves phase containing about 1 at.-%Sn. Some g-Fe 2 Nb 3 , which was associated with the alumina formation, was also found but did not contain tin. No Sn compounds were found with T i additions. T he experimental observations were compared with thermodynamic calculations performed using MT DATA software.MST /4255