As we blogged yesterday some environmentalists are questioning the ecological impact of biofuels. Now it seems they are also questioning the latest “alternative energy” source in Spain: Olive pips.
Some 300 buildings in Madrid are now being powered by the embers of burning olive stones. One of the companies involved in the scheme, Calordom is very enthusiastic. Its boss, Juan Cabello argues: “The energy is 100 percent non-polluting, a kilo (2.2 pounds) of burnt olive cores, in reality wood compressed in a natural fashion, emits the same quantity of carbon gas as they would if you just left them to rot.”
Not everyone is impressed though. Sara Pizzinato from Greenpeace says that “the carbon gas emitted to produce this energy must not be greater than that which it is then going to emit and that the energy generated by this combustible (product) must be superior to the energy utilised in creating this combustible.”
I’m sure this debate about the ecological impact of alternative fuels will run and run.
This sounds like a great idea, although I wonder how they deal with the potential for particulate polution. I think Pizzinato’s stance on this potentially helpful technology is not very constructive – unless she was quoted without sufficient context. What would happen to the olive seeds if they were not used for generating energy? They would probably be hauled off somewhere to a landfill, which takes energy too. However, there may be more to her quote than meets the eye; it’s a short article.
The rate of release of greenhouse gasses is an important consideration. If wood would take, say, ten year to naturally decompose and release captured carbon dioxide but gathering the wood and burning it would release that much carbon dioxide in one year, there is ten times more impact in that given year. If you keep doing that faster than new wood can be grown so as to sequester the gasses given off during burning, the net impact is an acceleration of greenhouse gas build up in the atmosphere.
Moreover, by burning the wood instead of letting it rot on the ground, carbon is being removed from the soil, which Guy Kirk of Cranfield University has reported in Nature has shown to be causing a significant acceleration of the Greenhouse Effect.
Finally, by growing more of a fuel wood and harvesting it, either crops or natural habitat is being reduced to make room for the wood lot, which has its own negative environmental and/or social impacts.
Ultimately, the answer the looming global energy and atmospheric warming crises is simple: we need to use a lot less energy.