Variable thermal cell array greenhouse envelope for energy-efficient food production

人们普遍认为，在需要粮食的社区附近的非耕地上建造温室可以缓解全球粮食供应问题。 然而，传统的透明温室结构在炎热或寒冷的气候中是不实用的，因为提供热控制所需的能量是过高的，并且在不透明的绝缘结构内电照射作物在经济上是不可行的。为了解决这个问题，我们开发了一种高性能的可变隔热系统，可以从日光透明窗切换到高度隔热的面板，使温室在大多数气候和季节都很实用。 我们的系统的高绝缘特性来自于我们的新型热电池阵列系统，该系统是一种高度可压缩的充气袋结构，该结构包含在密封的窗口面板内的轻质聚合物膜层的堆叠内。在其膨胀状态下，热单元阵列具有与固体聚苯乙烯泡沫塑料墙相同的隔热值，并且在其压缩状态下，隔热材料几乎消失，并且面板基本上充当传统的透明温室墙。虽然扩展和压缩阵列的方法可以使用马达容易地完成，但是这种设计也适用于新形式的静电致动，由此可以简单地通过向廉价的真空沉积薄膜施加电压来压缩阵列，从而消除机械马达部件。 在这个项目中，我们将展示和量化该系统的性能，以管理温室的内部温度在植物生长所需的范围内，而不使用能源用于加热或照明。本提案中所述的开发工作需要向加拿大温室产业内的潜在商业化伙伴证明这一潜力。

It is widely accepted that the global food supply problem can be alleviated by building greenhouses on non-arable land near the communities where the food is needed. Traditional transparent greenhouse structures, however, are not practical in hot or cold climates, because the energy required to provide thermal control is prohibitive and it is economically unfeasible to electrically illuminate crops inside non-transparent insulated structures. To address this problem, we have developed a high-performance variable insulation system that can be switched from a daylight transparent window to a highly thermally insulated panel, making greenhouses practical in most climates and seasons. The high insulation characteristic of our system arises from our novel thermal cell array system, a construction of highly compressible gas-filled pockets contained within a stack of lightweight polymer film layers contained within a sealed window panel. In its expanded state, the thermal cell array has the same insulation value as a solid Styrofoam wall, and in its compressed state, the insulation material virtually disappears and the panels essentially act as a traditional transparent greenhouse wall. While the method of expanding and compressing the array can easily be done using a motor, this design also lends itself to a new form of electrostatic actuation, whereby the array can be compressed simply by applying a voltage to inexpensive, vacuum-deposited thin films, thus eliminating mechanical motor parts. In this project, we will demonstrate and quantify the performance of this system to manage the internal temperature of a greenhouse within a range that is desirable for plant growth, without the use of energy for heating or lighting. The development work described in this proposal is required to prove this potential to prospective commercialization partners within the Canadian greenhouse industry.