returns the ideal enviorment would indeed be indoors. But the pods are not limited to indoor use only. You could stack em 3 high and however many you wanted to on just a open block of land. Fans , temerature gauges and timers would all be set to keep the pods at ideal temp and humidity, The growers know how to grow and an enclosed enviorment provides the best product and grow conditions regardless if housed in a large building or stacked on an empty lot, security would be no less either way as each pod can be locked