Light in action: Shining light on Dal research

This article first appeared in the Winter 2015 issue of Dalhousie magazine.

With 2015 designated as the UN’s International Year of Light and Light-based Technologies, we turn the spotlight on Dal’s light-related research and insight.

Cheaper solar

Rising climate change concerns and electricity rates have many homeowners exploring renewable energy sources. Solar panels are affordable but expensive to install: The necessary racks and wiring required can make solar energy generation a hefty investment. That’s why Ian Hill in the Faculty of Science is keen on re-examining solar cells and better incorporating them into materials already used in building construction. “We’re working on the next generation of solar cell technologies,” says Dr. Hill. His team is working on new solar cell materials and technologies that could be printed directly onto common building elements, like glass windows. What would that mean? With significantly lower installation costs (after all, homes need windows anyway), residential solar electricity generation becomes a lot more affordable. 

Improved mood

Canadians are used to cold and gloomy winter months. But fewer hours of sunlight can have a major effect on some vulnerable individuals, says Martin Alda, Dalhousie’s Killam Chair in Mood Disorders. Those with depression, bipolar disorder and other chronic mood disorders can experience worsening of their symptoms during times of reduced daylight in fall and winter. “Light is an important factor in mood regulation and it does play a role in mood disorders,” explains Dr. Alda. With light therapies in combination with other treatments, some people who suffer seasonal symptoms of mood disorders can successfully find relief.

Bright upgrades

With three campuses in Halifax and one in Truro, Dal has more than a few buildings to light. Between 2011-2013, “over 80 per cent of Dal buildings have been retrofitted with higher efficiency lamps, ballasts and some lighting controls,” says Rochelle Owen, director of the Office of Sustainability. It’s one of a number of energy-saving initiatives led by the Office of Sustainability and Facilities Management, with a goal to reduce Dal’s greenhouse gases by as much as 50 per cent by 2020. Next up: the Dalhousie Agricultural Campus in Truro, Nova Scotia, where testing of LED tube lighting has already taken place.

Staying sun safe

Harmful rays from sunlight are known to seriously damage the skin and lead to cancer. “UVA rays have a longer wavelength and can penetrate the skin deeply. But it’s felt that UVB rays have the potential to cause more damage,” explains Peter Green, with the Faculty of Medicine. UVB rays are more associated with sunburns but over-exposure to both UVB and UVA rays contributes to premature aging as well as cancerous changes in the skin. Dr. Green points out that any unintentional sun exposure is unhealthy, even if an individual tans easily. “In order to develop a tan, an individual’s DNA would have to be damaged to get there,” says Dr. Green. “A tan without damage is scientifically impossible.”