Grow fresh fruit and veg inside your home

Students from the Carnegie Mellon University (CMU) have developed a form of vertical farming that aims to help people in impoverished areas who have limited access to fresh produce.

Although it is widely assumed that fruit and vegetables are easily accessible in urban areas, nutritional islands within these urban settings are actually struggling to obtain these foods and maintain a balanced diet. The population have a diet consisting primarily of prepackaged, unhealthy foods from local stores which are not only expensive but they also lead to malnutrition and poor health.

To prevent people suffering both financially and nutritionally, a group of CMU students led by Jack Ronayne, an Engineering and Public Policy/Chemical Engineering undergraduate, tested inexpensive ways for people to grow fresh, nourishing food for their families inside their own homes. This project is one of many undertaken by the CMU chapter of Engineers Without Borders (EWB) in which the students identify and solve problems for communities across the world.

“Something we identified was this idea of nutritional islands in urban communities: places with limited access to fresh food either by distance, freshness or cost. We asked ourselves: could you simply grow fresh fruits and vegetables in your house?” said Kelvin Gregory, a Professor in Civil and Environmental Engineering and Faculty Advisor for EWB. “Obviously the footprint needs to be small, so you have to go vertical. And you’ll need to use artificial lighting. These are the problems we decided to solve for.”

While vertical agriculture is not a new concept, the students created a novel approach by using rapidly blinking LED lights. Since tomatoes grow leaves under these conditions, they used tomato plants as their first trial to grow nutritional food. The students managed to optimise the growing process by looking at exactly how much light was required to make the plant grow and using the least amount of energy needed to achieve the final product.

“LEDs are already more energy efficient than old-school halogen bulbs, but they also have the added benefit of being able to be turned on and off very quickly. So by rapidly flickering these lights at different speeds, we have been able to measure how much light is necessary to grow the biggest plant, using the least amount of energy,” Gregory explained.

The vertical agriculture method bears aesthetic similarities to a regular-sized bookshelf covered with a black plastic tarp and wired with lights, but its capabilities are wide-reaching. Inside a family home, the technology could grow up to 40 tomato plants, or for smaller plants taking up less space — such as lettuce — it could grow over 100. However, if afforded more space, the community-focused models can grow significantly more plants.

Gregory said that the technology will be implemented in Pittsburgh in a few years, with the hope of expanding its reach over time. He suggested the students will continue to work to provide everyone with access to fresh, healthy foods, regardless of their socioeconomic status.

“It’ll be about finding resources, going out to local foundations and setting up something that both serves the community and still allows for a research component.”