Federal and State Tax Incentives for Renewable Energy

More farms and nursery growers are turning to gasification wood heat because it is economical, environmentally friendly and renewable. Farms can take control of their fuel prices by sourcing wood from their land or from local suppliers. With a steady supply of affordable wood, farmers can produce year round to meet the growing demand for locally grown products.

Greenhouse Heating System Design

Heating for year-round greenhouse production requires designing a heating system that will meet the demands of growers and their production schedules. Whether it’s bedding plants winter greens, or cannabis, greenhouses require a continuous source of heat for cold season operation.  The key design elements for a wood heating system are based on local climate data, the amount of time between firings (if cordwood is used), and the delta-T (difference between outside temperature and the desired temperature inside the greenhouse).  FHS can design a system that will meet the loads on the coldest of winter nights to ensure that your product gets to market.

If you would like to reduce your reliance on fossil fuels and/or lower your operational costs, FHS can help you design and install a wood-fired hydronic greenhouse heating system that fits your production needs. Please contact us by phone or email and fill out our Greenhouse Specs and Crop Plan Form. We look forward to working with you.


The GARN WHS (wood heating system) is easily integrated into existing greenhouse and buildings or new construction. The boiler can provide heat through a number of systems — concrete radiant floors, in-ground radiant soil heat, bench heating and forced air units. It can also provide your domestic hot water.

The GARN’s cutting-edge technology is “simple, efficient, and durable” with over 30 years of experience and operation. With its patented, two-stage wood gasification technology, the system is virtually smokeless — which means clean air for everyone and a comfortable experience for users. The steel fuel chamber is easy to load and the door is always cool to touch. The GARN WHS is simple and easy to operate and to maintain because it’s made of just three moving parts — the handle, door and blower. The system is built to last indefinitely.

Wood Sources

GARN boilers can use any number of fuel sources: cordwood, slab wood, scrap wood, etc.   Fires in a GARN system burn hotter and require less tending than those in low-tech smoky boilers. Over a winter, a GARN wood heating system uses half the wood of a conventional wood boiler.

Thermal Storage

The key to the GARN system is thermal storage, meaning that the heat produced from the wood combustion is stored in water. With a GARN boiler, the fire does not burn constantly. In between firings, the insulated thermal storage tank stores heat that is available whenever your system has a demand. GARN boiler tanks range in size from 980 gallons to 3,200 gallons, to heat a range of spaces. When you turn a thermostat up, a pump draws hot water out of the thermal storage tank and into the heating system in your home, business or greenhouse.

Clean Air

The GARN WHS is virtually smokeless because it burns the wood quickly and cleanly with its two-stage wood gasification technology. The smoke that is produced in a GARN boiler not only doesn’t pollute the air, it is capitalized as a secondary fuel. A well-insulated combustion chamber needs steady airflow to achieve high-temperature combustion. A fan on the GARN system pulls outside air into the combustion chamber, where it is split into a top stream and a bottom stream. The bottom stream passes through the burning logs, engendering a very hot fire. The top stream skims the top of the combustion chamber, gathering with it the volatile burnable gases (smoke) given off by the burning logs. These two streams combine and are pulled into a second rear refractory lined chamber where the final very high temperature  combustion takes place.

Greenhouse Heating Design Form

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