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Closed Ecological Life Support Systems:

Why? A little background


A few Thoughts on our project

 The first space pioneer, a Russian by the name of Vladimir Vernadsky, who outlined the concept closed ecologies and raising food back in 1926 when he published "The Biosphere".

Today that concept has little application in space, for none of the missions have been of sufficient duration to warrant raising food. In the near future that will change, for missions will become longer and longer. In the not too distant future (hopefully well within the this century) there will be small colonies on the moon and Mars. These missions, and eventual colonies, will need food. The cost of importing food, air and water is prohibitive. Only the richest men in America could afford to live in space if they had to import all their consumables.

The solution to the high cost of shipping is to grow it. This is considerably more expensive in the short term because of the space that needs to be devoted to raising food. Even the most optimistic estimates have the amount of growing area needed in the tens of square meters; under normal field conditions on earth hundreds of square meters are needed to support a person. Enclosing this cubic {defined}will be very costly, but not as costly as shipping 15 pounds (7 kg) of food, air and water every day for each occupant. While we do not expect complete closure will be used in space colonies (much less shorter missions), 80-95% of the consumables can probably be raised in space.

The technology to raise this food does not yet exist. There have been a number of trials and the indications are that it will be possible to support people in space using CELSS {defined} technology, but closure has not yet been achieved. The most notable of the attempts at closure is Biosphere II {links}, but since they were looking more at earth ecosystem interfaces than CELSS, the data they obtained is not directly applicable to space missions. The Russians are some of the early pioneers of the technology, and had the first people to live in a closed system that was partially supported by CELSS technology. NASA {links} has also been doing extensive research on CELSS. While we are not officially associated with NASA, we have been in touch with many of their primary researchers.

Thus, while many are seeking to develop the technology, none have completed a Closed Ecological Life Support System. We find this somewhat odd, for the technology of farming is very advanced, and greenhouse technology is well developed. And a CELSS facility is little more than a farm in a greenhouse. When we first formed we wanted a project that was both within our capabilities and was a key to colonizing space. Developing closed system farms fit our criteria very well. So we chose building a completely closed ecological life support system, one that would be capable of supporting one or more people, as our first project.

A few comments from Ray (ISECCo President):

Any colonization effort involves import & export. One of the first things the early American pioneers did was to establish a food supply; it was just too expensive to ship food from point to point. Today we face a similar dillema in colonizing space; the food supply is just too expensive to ship. At 5 pounds (2.25 kg) per day to the surface of the moon, it would cost as much as half a million dollars A DAY to keep a person fed on the surface of the moon. And this does not take into account the 10 pounds (4.5 kg) of water and oxygen that need to be consumed along with food.

This creates quite a dillema for those who are enthusiastic about colonizing space. It is beyond the budget of all but a very few people to pay for just surviving in space, much less have luxuries like showers!

There are a couple possible solutions to this problem. First is to lower the cost of launching material into space. What are the limits to this? We could make two assumptions: first, we have to continue using rockets much as we have in the past. Currently it takes about 60 units (eg pounds, or kilograms, or ounces, or megatons) of fuel to put one unit into low earth orbit (that would equate to about 420 units of fuel to put a single unit onto the surface of the moon.) So we can see that in order to make it cheaper to get to space either we need a very low cost (per unit) for fuel, or we need to improve the efficiency of our rockets.

Since rockets are currently pretty efficient (and I am completely ignoring the fact that the majority of our cost now--as in over 99%-- is for the launch and support of the rocket, not the fuel; I assume that when millions of people are going to space the costs associated will be like those of airlines: primarily fuel) I doubt we can improve their efficiency much further. For example if you boost the shuttle main engine pressure very much above what it is, you can no longer burn hydrogen and oxygen to make water because the pressure keeps them from forming! The cost of fuel is now relatively cheap. So I don't see much hope along that line either.

So what about some other means of accessing space? There are a number (mass driver; space elevator; 'flying' to space; etc) that have a lot of potential. But even then you still have to get from low earth orbit to your final destination (eg the moon). So I don't see overall transportation costs coming down a huge amount.

This means you must reduce the cost of living and working in space. Biosphere technology and Closed Ecological Life Support Systems are the key to this.

When we first formed our goal was to do something meaningful for space colonization; we didn't want to be just another group that sat around and day dreamed. After examining our resources, what other groups (be it government or private) were working on, we perceived that research on closed life support was sadly lacking. So we selected as our first project a closed ecological life support system.

Copyright © Fall 2007