Effects on ECLSS Behavior caused by the Start-up of a Food Production Facility

Abstract

In the next decades humans will take on the challenges of venturing to the Moon, Mars and other planetary bodies in our solar system. The farther out and the longer the crewed missions get, the more effective is recycling of resource to provide life support for the humans travelling. One aspect is the production of food on-site during the mission to greatly reduce the resupply need from Earth. The cultivation of plants hereby is the preferred way. Plants do not only provide a large variety of food, but also consume the carbon dioxide exhaled by the crew and produce oxygen. The cultivation of plants in a closed environment is challenging, but recent experiments on Earth and on-board the ISS have shown the feasibility of such a system. Another aspect of plant cultivation in a crewed spacecraft or habitat is the influence of the crops on the ECLSS. Food production is only possible, when the plants are provided with the resources and environment necessary to thrive. Providing these resources in sustainable way means that the greenhouse subsystems are interconnected with the ECLSS. Consequently, the cultivation of plants has, depending on the amount of crops grown, a significant impact on the ECLSS (e.g. on the dimension of certain systems like the water recycling). This paper presents the results of a dynamic simulation of an ECLSS with an integrated greenhouse for crop cultivation. The focus lies on the start-up phase of this facility, because until the steady-state production is reached the impact of the greenhouse on the ECLSS is changing constantly and therefore the ECLSS has to cope with that. The simulations show that the startup of the greenhouse after the crew arrival with staggered sowing performs best, because this scenario has the best system behavior and does not need additional automation equipment and procedures for sowing and harvesting.