Commercial Biomass Boiler Systems

Froling Energy designs wood pellet and wood chip heating systems that meet—or exceed—all government regulations, industry standards and client goals.

Commercial buildings in New England have significant heating loads costing thousands of dollars each year. Typical schools and commercial buildings consume between 4,000 and 25,000 gallons of oil. Groups of buildings such as private school campuses or municipal complexes can use as much as 50,000 gallons of oil.

These are all situations where biomass boilers can be quite competitive with “conventional” oil or propane boilers, using wood pellets or PDCs.


Systems Design and Planning

We start by carefully reviewing the project’s objectives, site requirements, budget, and schedule, while also analyzing calculated heating loads, existing equipment and historical fuel consumption data. Are your existing fossil-fueled boilers at retirement age? Do you have problems coping with your buried oil tanks?

In nearly every commercial situation biomass boilers are paired with oil or LP-fired boilers that play a peaking and backup role. Usually we size the biomass boiler to cover about 65% of the design load while the oil or LP boiler can cover 100%, however the quantity of heat provided by each of these is very different. With this configuration, the biomass boiler provides 90-95% of a buildings annual heat requirement while the oil or LP boiler does just 5 to 10%. This sizing is best for many reasons, especially for keeping the initial investment affordable.


We calculate system efficiency based on real-world use, because equipment is seldom run at peak output or efficiency all the time.

We improve the efficiency of boiler room equipment and design by replacing heat distribution circulators and fossil fuel boilers with new, energy efficient variable speed models.

Most of our commercial and school systems employ new or existing oil or propane fired boilers to act as peaking boilers as well as providing fully redundant backup capability.

Heating System changes must be analyzed using BOTH the future cost of fuel and the cost of the equipment changes. You are considering optional futures:  sticking with oil or adding Biomass. We recommend looking 10 to 20 years into the future with every possible option.

Our analysis includes space heating, the production of domestic hot water and future changes like an addition or the inclusion of improved ventilation.

Which wood fuel is best?

A general rule is: The larger the consumption of fuel, the more practical it is to use less refined, less costly fuels. However, there are a number of other factors that influence a biomass fuel decision such as fuel availability, access for delivery trucks and the distance between the boiler room and potential fuel storage locations.

Green wood chip systems have a much higher up-front cost but because they cost even less, in large scale, where heat demand is more than 8 million BTUs per hour, they can be the most cost-effective solution.

On the other hand, boilers that burn more refined fuels like PDCs and wood pellets have proved themselves to be more reliable, economical and trouble-free.



Modular biomass boiler room

A Biomass boiler system can be set up to work seamlessly with a fossil fuel boiler that is retained for full redundancy or for use during peak demand periods. Keeping fossil fuel boilers can reduce the overall investment by reducing the output capacity required of the more costly pellet boilers.

We can construct modular, prefabricated “containerized” systems that integrate boilers and fuel storage in a movable boiler house that can be moved to your site, craned into place and quickly commissioned. We choose the solid fuel that best suits your site, situation, and economics—wood pellets, PDCs or green wood chips.

Large-Scale Systems

3000 gallon biomass buffer tankThis 3000-gallon buffer tank works with the boiler to provide a steady supply of heat and hot water to two adjoining facilities. Large-scale biomass systems are an excellent investment for any building or group of buildings that is consuming over 50,000 gallons of oil per year. Designers of such systems can choose from amongst the three main biomass fuels but it is quite likely that the least costly fuels, PDCs and green wood chips, will be selected.

Large scale systems are built around biomass boilers that have heat outputs of upwards of 1 million BTU/hour such as the Schmid UTSK, the Viessmann Vitoflex 300-UF, and the Fröling Turbomat. The advanced technology and designs of these boilers bring many advantages and real-world benefits.

  • Automatic ash removal from the boiler and cyclone
  • Very low particulate emissions without ESPs
  • Minimal staff maintenance tasks—weekly, not daily
  • Remote monitoring and fault alerts by email—standard
  • Proven designs that are repairable and easy to work on
  • Self-igniting with automatic modulating heat output

We work with the following biomass boiler manufacturers for commercial systems