Cleantech news as it happens — check back for regular updates:

• Researchers at Israel’s Weizmann Institute of Science have devised a unique new mechanism that uses light to break up water into hydrogen and oxygen without the need for sacrificial chemical agents;
• Danish wind-energy firm Vestas has begun a long-term technology partnership with the University of Wisconsin-Madison’s College of Engineering;

• Tesco has launched a six-week, two-store trial that gives customers the opportunity to remove and leave excess plastic and paper packaging in store after making their purchases;

• Electricity-related carbon dioxide emissions in Spain fell by 24 percent in the first quarter of this year as the economy contracted, Point Carbon reports;
• Black carbon, a particulate pollutant created by the incomplete combustion of fossil fuels and biomass fuels, is responsible for about half of the observed warming in the Arctic over the past century, according to a new study.

• Green technology investors seek safer havens in 2011
• New US consortium plans $1.4bn in cleantech investments
• What does 2011 hold for China, US?
• World Economic Forum: Cleantech rules
• Virtual design speeds green reality
• Opinion: Darling’s green bank idea is laughably small
• Some guys and Holy Grails: 5 rules for spotting ‘cleantech porn’
• Despite some ‘green shoots,’ cleantech VCs see trouble ahead
• Cleantech Connect Awards recognise fast-growing innovators
• Irish cleantech firms seek opportunities in Silicon Valley