Pumps and Pipes

A Taco 007
A Taco 007, shaken not stirred.

“Will the 007 be enough?”  is a common question in early spring as greenhouses around the region fire up and we do our best to keep seed trays and their cargo warm on the still-cool nights.  My mind instantly goes to “which movie?” And then I crash back to earth and realize this is a question about pumps and I am not Q. Continue reading Pumps and Pipes

Thermostats for Agriculture

I am often asked by growers and processors to recommend a thermostat for a greenhouse, cooler, or postharvest process use.  There are many to choose from and their specifications can be confusing. It is important to remember just what a thermostat does. It is essentially no different from the light switch on the wall with one very significant exception.  Instead of depending on a person to switch it from ON to OFF, we use a temperature measurement.  The accuracy of both the temperature setpoint (what you set) and the actual temperature (what the actual condition is) can be critical for production quality and energy efficiency. Continue reading Thermostats for Agriculture

Vermont Farmers Food Center Heats with Biomass

Rob Steingress (VFFC), Bill Kretzer (12 Gauge Electric) and Greg Cox (VFFC) perform final inspections before the initial firing of the boiler.
Rob Steingress (VFFC), Bill Kretzer (12 Gauge Electric) and Greg Cox (VFFC) perform final inspections before the initial firing of the boiler.

UVM Extension and others supported the recent installation of a 341,200 BTU/hr (output) multi-fuel biomass boiler at the Vermont Farmers Food Center (VFFC) in Rutland, VT.  The boiler heats the Farmer’s Hall building with the capability to use several alternative fuels to displace propane. The boiler was fueled primarily on wood pellets but was also able to feed and burn grass biomass pucks. This demonstration project carried a cost premium when compared to a typical propane heater installation.  That premium is paid back over time due to recurring fuel cost savings. A simple payback period of 2.2 to 8.0 years is feasible against a cost premium of $51,255 for the boiler depending on the fuel used and the amount of use. For more details about the project and the economic performance please see the report.

Continue reading Vermont Farmers Food Center Heats with Biomass

Grass and “Ag Biomass” Competitive with Wood Chips

Chris Davis (Meach Cove Trust) prepares the boiler and combustion testing equipment for a trial run of the new fuel.
Chris Davis (Meach Cove Trust) prepares the boiler and combustion testing equipment for a trial run of the new fuel.

Recent testing at the Meach Cove Trust has demonstrated strong economic and technical feasibility of grass-based biomass combustion fuels.  The use of solid, densified, cellulosic biomass fuels has been well demonstrated with wood pellets in residential and light commercial systems and wood chips in larger, often centralized systems.  The Grass Energy Partnership of the Vermont Bioenergy Initiative has been exploring an alternative form of fuel; grasses densified in a specially developed processor to take the form of 1.5”-2.0” round cylindrical pucks.  Grass fuels may be produced on otherwise marginal agricultural land, sometimes in perennial production and even in buffer strips offering environmental benefit.  Additionally, fuel can be made by densifying agricultural residue or biomass harvested from idle pasture or fields.  We have referred to this fuel as “Ag Biomass”. The testing summarized in this report has demonstrated the technical and economic feasibility of such fuels.

Continue reading Grass and “Ag Biomass” Competitive with Wood Chips