Where algae, garbage are energy sources
IT was thought that only Filipinos experienced some spine-tingling fear with the mere mention of the spiraling cost of energy. We are not alone.
Residents of two advanced cities in Western Europe are already making full use of unlikely alternative sources of energy – algae and garbage. While those in two American cities are banking on solar power and wind power. These people are already anticipating that the traditional sources of power – fossil oil and natural gas – will not be forever.
The New York Times International Weekly, weekend supplement of the Manila Bulletin, June, 2013 issue, reported that in the city of Hamburg, Germany, a new modern apartment complex has introduced the latest technology in sustainable building by setting up a vertical algae farm. The edifice relies entirely on renewable energy.
Its designers said the building “will harvest fast-growing algae to create biofuel, produce heat, shade the building, abate street noise, and make history.”
And, meantime, Oslo, the capital of Norway, is often mocked as “the city that imports garbage.” Its suppliers are England, Ireland and Sweden. The wastes are converted by huge incinerator plants into heat and electricity.
The capital is regarded as a recycling-friendly city. Most of its schools are heated by burning garbage from household trash, industrial waste, even from dangerous wastes from hospitals and drug arrests. But it has run out of garbage to burn. Thus, it goes into importing wastes from nearby countries.
The report says: “The problem is not unique to Oslo, a city of 1.4 million people. Across Northern Europe where the practice of burning garbage to generate heat and electricity has exploded in recent decades, the demand for trash far outstrips supply.”
Back to the algae-powered building in Hamburg: “Mounted on the sides of the building are 129 bioreactors, flat glass panels on exterior louvers that serve as an environment for the algae to flourish.”
“The algae are fed liquid nutrients and carbon dioxide to spur growth. Pressurized air is pumped into the panels to further increase growth. The panels double as solar thermal collectors to convert sunlight into usable energy,” notes the weekend supplement.
Extra light not absorbed by the algae during photosynthesis is converted into heat. It can either be used immediately for hot water or stored underground.
In the United States, some solarpowered airplanes before could only fly during daytime when there was sunlight. Now an innovation of such aircraft has been developed in Mountain View, a city in California.
Christened Solar Impulse, this one stores solar energy so it can fly even at night.
Admittedly, commercial flights of solar-powered aircraft are still years away. Experts are eyeing this innovation for drones which today risk damage during landing for refueling. Drones are now used for military as well as for civil- ian purposes. Some technologies that have been developed for Solar Impulse have commercial prospects, notably, the batteries that store the solar energy, and the foam that insulates them.