EES Blog

A miniature biofuel cell can generate electricity using the sugars in grapes, according to researchers in Japan.

The device has a needle bioanode that can be inserted into the grape, and a gas diffusion biocathode that uses oxygen in the air to oxidise the sugars. The maximum power produced was 26.5µW at 0.34V, which was used to power a light emitting diode (LED), which indicated the level of sugar in the grape.

The device could be used in the same way to test blood sugar levels (a test was done by inserting the needle into an animal vein) to monitor health.

Read this exciting EES paper now:

Enzymatic biofuel cells designed for direct power generation from biofluids in living organisms
T Miyake, K Haneda, N Nagai, Y Yatagawa, H Onami, S Yoshino, T Abe and M Nishizawa,
Energy Environ. Sci., 2011
DOI: 10.1039/c1ee02200h

Researchers in the US and Canada simulated solar radiation management (SRM), a form of geo-engineering that involves reflecting sunlight to reduce global warming.

Suggested approaches are to increase the amount of light-scattering stratospheric aerosols or increase the reflectivity of low-altitude marine clouds. The idea has attracted renewed interest but there are enormous uncertainties about the risks and effectiveness of SRM.

 The team used a HadCM3L programme for the simulations and came to the conclusion that solar geo-engineering could be tested to reduce uncertainty about climate response, but tests would require decades of modulated climate forcing.

 Read the EES article today hot off the press!

Can we test geoengineering?
D G MacMynowski, D W Keith, K Caldeira and H-J Shin,
Energy Environ. Sci., 2011
DOI: 10.1039/c1ee01256h

Scientists are attempting to reduce the costs of harnessing the sun’s energy by creating ceramic tiles that can perform photovoltaic action, so-called “solar tiles” that can be used to tile roofs.

Hugo Aguas, Rodrigo Martins and their research group at Universidade NOVA de Lisboa and UNINOVA have successfully fabricated solar tiles and demonstrated market viability with a cost estimation.

Their new solar tiles were able to achieve a 5% conversion efficiency and 80% quantum efficiency.

Read the EES article today:

Silicon thin film solar cells on commercial tiles
H Aguas, S K Ram, A Araujo, D Gaspar, A Vicente, S A Filonovich, E Fortunato, R Martins and I Ferreira
Energy Environ. Sci., 2011, DOI: 10.1039/c1ee02303a

Scientists are looking into the safety of lithium ion batteries so that they can be used to power large devices such as cars or power grids.

Lithium ions are OK for use in small devices, such as laptops and phones, but there is a risk of fire if they need to power devices with higher energies.

Scientists from France have used a fire calorimeter – a device recognised by US and EU regulating bodies – to get an insight into the fire behaviour of these batteries.

The apparatus provides online analysis of mass loss and combustion gas production (O2, CO, CO2, hydrogen halides, HCN, NOx, SOx, aldehydes, THC). From these data, the rate of heat release, heat of combustion and the mass of burnt products from the combustion tests could be deduced. The data could help in fire simulation tests, say the researchers. They add that the identification and quantification of toxic emissions from combustion gases can be estimated.

As a result, the data could play a part in improving the safety of batteries, they conclude.

Read the Energy & Environmental Science paper today:

Investigation on the Fire-Induced Hazards of Li-ion Battery Cells by Fire Calorimetry
P Ribiere, S Grugeon, M Morcrette, S Boyanov, S Laruelle and G Marlair
Energy Environ. Sci., 2011, DOI: 10.1039/c1ee02218k