Growing cannabis indoors is staggeringly energy-intensive. According to some estimates, the marijuana industry accounts for as much as 1% of all the energy consumed in the United States.

With multiple states poised to legalize recreational cannabis this year, and both the medical and rec markets continuing to experience rapid growth, the race to find solutions to cannabis grower's energy problems and reduce the environmental impact, is on.

Here are three areas in which there's room for the industry to truly go green.

1. Hydroponics

In a hydroponics operation, plants are grown in sand, gravel, or water with recycled nutrients, as opposed to soil, a process that requires fewer artificial minerals and pesticides. They also require less space, meaning they can be located in urban areas close to markets. "This has a huge impact on reducing the carbon emissions produced by needing to transport produce from one location to another," writes Charlotte Rennick in Simply Hydroponics.

From a grower's perspective, a hydro setup requires more initial investment for hoses, pumps, baskets, rock wool conditioner, and a host of other necessities - but it also produces more uniform buds and a faster grow, in addition to reducing greenhouse gas emissions. It's also easier on water consumption than growing in soil.

2. LED lights

LEDs have revolutionized indoor growing, which in the past often used, as journalist Renee Lewis points out, "1000-watt, high-intensity bulbs, [generating] a lot of unwanted heat that then has to be removed from the indoor environment with air conditioners and ventilation systems," .

In addition to emitting almost no heat, LEDs consume up to 70 percent less power than once-common HID, or high-intensity discharge bulbs. They're good for the plant, as well as the planet: since LED grow light diodes use only the necessary wavelengths in the correct ratios necessary for photosynthesis, they result in a higher yield.

LED lights can also last about 100 times as long as traditional bulbs, and 6-7 times as long as compact fluorescent lights.

3. Energy monitoring

"The industry hasn't come to full fruition yet," Boulder-area land use sustainability examiner Ron Flax told Al Jazeera. "To some extent the industry hasn't known how much energy it's consuming … by installing energy-monitoring devices they have a tool to see in real time how much power they're consuming - an important first step for anyone wanting to improve."

Legalization would represent a massive step forward for the planet, as well as cannabis consumers, since the energy grid tends to run almost entirely on fossil fuels during peak consumption hours, giving growers the information they need to concentrate the lion's share of energy use around non-peak times. It would be a massive coup when it comes to reducing emissions.

Other states might also follow the example of Boulder County, which has established an Energy Impact Offset Fund requiring commercial cannabis growers to either offset their electricity use with renewable energy, or pay a 2 cent charge per kWh: the fund is then used to educate growers on best cannabis cultivation practices with regards to energy usage, as well as to fund renewable energy development initiatives.