sexta-feira, 26 de fevereiro de 2010

Solar Panel Productivity Boosted by Origami
Three-dimensional solar panels could in principle absorb more light and generate more power than a flat panel of the same area footprint, which could prove useful in circumstances where the available space is limited. The idea is that any light that might normally reflect unused off a solar panel surface could then get trapped on another panel.
Original paper at Applied Physics Letters
World's largest solar-powered boat unveiled
PlanetSolar [built at the Knierim Yacht Club in Kiel in northern Germany], a 31 x 15-metre white catamaran, has been designed to reach a top speed of around 15 knots, equivalent to 27 kilometres per hour, and can hold up to 50 passengers. (...) PlanetSolar will launch in late March before starring at Hamburg port's 821st anniversary celebrations in May and undergoing testing between June and September.

quarta-feira, 24 de fevereiro de 2010

Moura: Inaugura laboratório de investigação e ninho de empresas
São inaugurados hoje, no Parque Tecnológico de Moura, o laboratório de investigação na área da energia fotovoltaica e o centro de acolhimento a microempresas. O laboratório de investigação, afecto à Lógica, E.M., está equipado com tecnologia de ponta e apto para fazer ensaios e certificação de tecnologia para aproveitamento da energia solar. O centro de acolhimento é uma iniciativa conjunta da autarquia mourense e da Associação “Rota do Guadiana”, possui seis espaços para oficinas, quatro gabinetes para serviços e uma sala de formação. O investimento foi de 530 mil euros, financiado em 70 por cento pelo Interreg e os restantes 30 por cento pela Câmara de Moura.

Solar news from the USA

The US Department of Energy (DoE) will support construction of three utility-scale concentrated solar power plants. Energy Secretary Steven Chu says the conditional commitments for US$1.37 billion in loan guarantees to BrightSource Energy will support 400 MW of capacity using the company’s concentrated solar power technology. This capacity will double the existing generation capacity of concentrated solar power in the USA.The three-plant Ivanpah Solar Complex will be located on federally-owned land in the Mojave Desert in southeastern California, near the Nevada border, and could be the world's largest operational concentrated solar power complex.
[In the meantime] The Center for Revolutionary Solar Photoconversion (CRSP) has funded 10 advanced solar research projects totaling US$800,000 in its second round of Shared Research Program funding.

domingo, 21 de fevereiro de 2010

Maternidade construída na Guiné-Bissau
[A Associação de Cooperação com a Guiné-Bissau, colectividade de Viana do Castelo] quer concretizar sonho de uma década e dotar centro de saúde de Cacheu, na Guiné-Bissau, de uma pequena maternidade.(...) O Rotary Clube de Viana do Castelo e o de Bissau viram, também, aprovado um projecto no valor de cerca de 300 mil euros, verba que servirá para apetrechar a maternidade e o centro de saúde de Cacheu. De acordo com Carvalhido da Ponte, o apoio do Rotary servirá, ainda, para instalar um sistema de energia solar na futura unidade de saúde, bem como para dotar 20 salas de aula de carteiras, cadeiras e restante equipamento escolar.

sexta-feira, 19 de fevereiro de 2010

More record solar cells

Mitsubishi Electric announced that it has achieved a record conversion efficiency of 14.8% in a 5mm x 5mm [triple junction] thin-film silicon photovoltaic cell. [The same company also announced] a 19.3% efficiency rating for a practically-sized polycrystalline silicon PV cell of 100 squared centimeters or larger, with the PV cell measuring approximately 15 cm x 15 cm x 200 micrometers (...) The second world record, achieved with the same technologies [basically reducing the resistive losses] in an ultra-thin polycrystalline silicon PV cell measuring approximately 15 cm x 15 cm x 100 micrometers, is an efficiency rating of 18.1%.
Kyocera Corporation announced that it has achieved a new world record of 16.6% module efficiency (aperture-area efficiency of 17.3%) for multicrystalline silicon solar modules using 54 cells in the development stage. To achieve this record, Kyocera further improved its proprietary "Back Contact" technology and module design to optimize the performance of each cell, thus increasing overall energy conversion efficiency. [Kyocera had announced an energy conversion efficiency of 18.5% for individual solar cells in the development stage.]

quarta-feira, 17 de fevereiro de 2010

Lei da certificação energética deu um novo impulso às energias renováveis

Portugal entre os mais rápidos na eficiência energética dos edifícios
Em cinco anos, a maioria das casas portuguesas vai exibir painéis solares. É a visão do arquitecto Guilherme Carrilho da Graça, especialista em eficiência energética. Apesar de alguns atrasos, "a nível europeu, Portugal e Irlanda estão à frente na implementação do sistema de certificação energética dos edifícios" (...) "A certificação energética teve um papel excepcional na promoção da energia solar térmica para aquecimento de água sanitária, uma vez que só se atinge o A+ [nota máxima] com essa componente. Juntando a isto um melhor isolamento, esta é a grande mudança que a classificação [em vigor desde 2007] trouxe aos investidores", assegura o arquitecto.

terça-feira, 16 de fevereiro de 2010

Enhanced absorption and carrier collection in Si wire arrays for photovoltaic applications
To achieve competitive conversion efficiencies, [silicon nano-]wires must absorb sunlight over a broad range of wavelengths and incidence angles, despite occupying only a modest fraction of the array’s volume. Here, we show that arrays having less than 5% areal fraction of wires can achieve up to 96% peak absorption, and that they can absorb up to 85% of day-integrated, above-bandgap direct sunlight. In fact, these arrays show enhanced near-infrared absorption, which allows their overall sunlight absorption to exceed the ray-optics light-trapping absorption limit for an equivalent volume of randomly textured planar Si, over a broad range of incidence angles. We furthermore demonstrate that the light absorbed by Si wire arrays can be collected with a peak external quantum efficiency of 0.89, and that they show broadband, near-unity internal quantum efficiency for carrier collection through a radial semiconductor/liquid junction at the surface of each wire. The observed absorption enhancement and collection efficiency enable a cell geometry that not only uses 1/100th the material of traditional wafer-based devices, but also may offer increased photovoltaic efficiency owing to an effective optical concentration of up to 20 times.