

Air New Zealand is the latest airliner to test a new biofuel








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RE: Green gooey algae is our friend
By gerf on 1/1/2009 10:41:04 AM , Rating: 3
Have you considered the amount of expense in large water holding containers as compared to soil?
1. The container needs to be built. It will need to be relatively heavy duty to hold as much water as you plan, and also clear. So we're looking at large amounts of plastic.
2. The weight of the container on a building is very large. Most roofs won't hold nearly that much weight. Even in the weird event it would, the building structure itself would need to support it as well, as well as the foundation.
3. Algae may produce bio-stuff, but it still needs to be pumped and processed quite a lot.

So is it worth it to have a cube of water on your roof yet? I doubt it.

RE: Green gooey algae is our friend
By Samus on 1/1/2009 7:10:40 PM , Rating: 2
Coming from a horticulure background specializing in hydroponics...

1. only the walls need to be white. the top of the container needs to be clear (obviously) but water is extremely refractive at shallow depth and the walls will reflect a decent spectrum for balanced vegetative growth.

2. Most containers are made out of PVC plastics. Water is 99% of the weight. Since you will be growing a shallow depth, lets say 1 meter, on a large rooftop, say 10 meter x 10 meter, would be apx. 3.3 tons water. Most buildings have close to this much weight on them already when accounting for HVAC, communications, etc. Keep in mind, 3.3 tons is the weight of two cars. Some buildings can support construction equipment (15-ton crains!) during construction projects.

3) no arguement. except to have these containers built on the rooftops of building with processing equipment on-site.

By BZDTemp on 1/1/2009 7:31:44 PM , Rating: 2
10 meter x 10 meter x 1 meter = 100 cubic meter. one cubic meter of water is 1 ton so how do you make it 3.3 tons?

If you want a 10 meter x 10 meter tank to weigh only 3.3 tons you will need it to be very shallow indeed. In fact it would have to be less than 3.3 centimeter to account for the weight of the tank itself.

