Vertical axis wind turbines

Difficulties hampering the use of small-scale wind turbines in cities include a) the roughness of the urban terrain and skyline, and the resultant effect on winds, b) high directional variability of winds, c) greater wind turbulence, and d) the more complex resulting wind flow characteristics. Vertical-axis wind turbines have a distinct advantage in such environs, as they are omnidirectional, whereas horizontal-axis wind turbines must face the oncoming wind to capture energy. Areas having ‘urban heat island’ effects show increased wind speeds as well, further improving the prospects for urban wind turbines.

The UK government adopts this sustainable development focused, anthropocentric approach to urban regeneration. They believe that sustainable development must “ensure a better quality of life for everyone, now and for generations to come” (DETR, 1999). They have set four objectives aiming to ensure sustainable development. However, the three environmental objectives are vague whilst the fourth is more directive in committing to the maintenance of high and stable levels of economic growth. This suggests that the UK government has adopted a 'weak' or 'light-green' interpretation of sustainability allowing the long-term viability of economic growth to be balanced against the environmental objectives.

Chemically modified wood is wood that has been impregnated with a benign chemical substance, then heated to cause chemical changes to the wood that result in similar improvements in dimensional stability and durability. Acetylated wood is a chemically modified wood, one altered via the impregnation of liquid acetic anhydride under heat. Since all woods naturally contain a certain amount of acetyl groups — the chemical compound central to the acetylation process — nothing new or toxic is being added to the wood by this chemical modification.

Current utilization rates for data center servers, storage and other assets are as low as 6 percent, and facilities utilization rates average less than 60 percent, according to the GeSI report. The key to realizing increased IT and data center efficiency potentially resides with current trends toward the adoption of hosted services (outsourcing and cloud computing), server and storage virtualization, and low-energy cooling as a means to replace less-efficient data centers and application services, deliver business continuity and address demand elasticity.

Furthermore, acetylation alters the chemical structure of the wood and is irreversible; the acetylated wood will never leach or give up its treatment. And, since acetylation fully penetrates the wood, there remains no untreated wood to be exposed by any cutting or machining. The wood is treated uniformly to its core.

The first metric of sustainability is demand, both by the university lecturers, as well as by students, career professionals, and governments. If demand is high and is seen to be usefully met, the institutional, human and financial resources needed to meet it are more likely to be mobilized over time.