Let’s say you have a small room with four 1,000W HPS grow lights. Your four lights alone create 16,000 BTUs of heat that need cooling. If you trade those lights in for four 630W fixtures, which will match, if not exceed, your current yields, you will only create 10,000 BTUs of heat. Your air conditioner won’t have to run as often, and you’ll see savings on your power bill. The low heat output of CMHs make them an ideal choice for small grow spaces, such as closets and grow tents.
Another benefit is that with the ballasts required to run them, you won’t have to deal with the electromagnetic interference (EMI) issues many growers experience with digital ballasts. High levels of EMI from digital ballasts are known to interfere with cellphone service, radio, Wi-Fi and cable television, and the Federal Communications Commission hands out citations to people who violate EMI emission standards.
One final advantage ceramic metal halides bring to the table is their superior light quality compared to other HID lamps, which is due to a few factors. First, they have a wider spectrum than other HID lamps—a result of the near-perfect, unique combination of salts, halides, and gases used in the arc tube.