Sustainable Practices

 

Forward thinking with Peoples Gas and Pittsburgh Water and Sewer Authority (PWSA).

 
 

You never change things by fighting the existing reality. To change something, build a new model that makes the existing model obsolete. 

—Buckminster fuller

Over the past two years, we have invested a great deal of time experimenting with potential ways of growing food. Using very basic materials–poles, burlap bags, recycled cans, and olive containers—we grew an enormous amount of produce, which was shared with the community. The site is, in fact, ideal for growing food in summer months, but expansion of the growing period is necessary if we want to have any impact on food insecurity and access.

We also experimented with ways to control and collect storm water runoff to use for irrigation. Working alongside Pittsburgh Water & Sewer Authority (PWSA) helped us understand that the impervious roofs and paving at our site contribute to an estimated annual 137,916 gallon load to the City’s sewer system. To address this issue we designed a solution that uses an underground cistern, channeled to a bioretention swale for percolation and evaporation. The cistern will collect, store and use rainwater for irrigating our greenhouse and outdoor vertical garden.

 Combined cooling, heating and power (CCHP) provides on-site, independent power system that revolutionizes kitchen and greenhouse efficiencies.

Combined cooling, heating and power (CCHP) provides on-site, independent power system that revolutionizes kitchen and greenhouse efficiencies.

A partnership with People’s Gas has led to a plan to install a new, innovative system—a combined cooling heat and power (CCHP) system. The CCHP system generates electric power in the same way as traditional electric generators but it also captures and supplies heat, making it more efficient and less carbon intensive. The CCHP to be installed by People’s Gas will initially run on natural gas, but long-term, our plan is to use composting to create renewable natural gas (RNG – also known as biogas). In that way, the system becomes self-contained and sustainable. The CCHP will provide heating, cooling and electrical power for the bakery (oven, lights, equipment), and carbon dioxide (C02) for a hydroponic greenhouse to be erected on-site.

The CCHP system gives us the potential to extend our growing season. In addition to providing energy to run the baking kitchen, the CCHP system will provide [heat, cooling, carbon dioxide (CO2)], and power to the greenhouse. Gas engines are highly efficient at providing the stimulus for the growth of plants, while also providing a flexible supply of electrical power. Heat, light and carbon dioxide (CO2) all promote plant growth. Gas engines provide electrical power at the alternator and when in a cogeneration configuration can also recover useful heat. Carbon dioxide is released in the exhaust gases of the engine as a by-product of the combustion of the fuel gas. Electrical power can be used to provide energy for lighting or can be exported to the grid, heat can be stored as hot water for use when needed, and finally the CO2 can be scrubbed and used to promote plant growth.