Q: So how many corn cobs (a type of biomass) does it take to power a house?
A: Some rough approximations: Assuming the average US house uses 32 kWh/day (EIA data)
Corn cobs are a biomass fuel in the natural state; therefore, one expects some variability in the Heating Value of one batch of cobs vs another.Assuming a reasonably HIGH HV, it would take about 64 lb/day to power this average home.Assuming a relatively LOW HV, it would take about 85 lb of cobs/day. The above assumes that the biomass is converted by a genset with some engine of "average efficiency".
So, let's just take the middle road and say it takes about 75 lb of corn cobs per day to power an average home. We will have actual data on power production/lb of cobs in about 3 months.
The genset is a Cummins Power Generation model DSGAA. It's a 100 kW generator driven by a 6.7L Cummins diesel engine. The engine is an in-line six, turbocharged with air-to-air intercooler. Gross hp is 250 in standby mode, and 217 in prime mode.
The only modification to the engine was to the speed control. Otherwise, it's just as it came off the assembly line.
Producer gas does not work well (if at all) in a diesel engine. In this application, there is a small amount of diesel fuel being injected along with the producer gas. We can run reliably at <10% diesel and are aiming for 5%/95% diesel/producer gas.
Center for Diesel Research, U of M Twin Cities
All Power Labs, LLC - builder of the PowerTainer and designer of the gasification technology
Cummins Power Generation, supplier of the genset and engineering advice
HGA Architects and Engineers, consulting engineers
The University of Minnesota, Morris is a national leader in sustainable energy and green living. As a leader, Morris is at the forefront of new sustainable energy technologies, such as the PowerTainer—a transportable diesel engine generator (genset) powered by biomass (DIESEL POWER NOTE: We have used biomass energy, or "bioenergy"—the energy from plants and plant-derived materials—since people began burning wood to cook food and keep warm. Wood is still the largest biomass energy resource today, but other sources of biomass can also be used. These include food crops, grassy and woody plants, residues from agriculture or forestry, oil-rich algae, and the organic component of municipal and industrial wastes. Even the fumes from landfills (which are methane, the main component in natural gas) can be used as a biomass energy source.. —Definition of biomass from NREL)
The unit, completely housed in a standard 20 foot shipping container, is the result of a partnership among the University of Minnesota, Morris, Cummins Power Generation, and the University of Minnesota Center for Diesel Research. The unit was built by All Power Labs in Berkeley, California. Funding for the project was provided by the National Energy Technology Laboratory (U.S. Department of Energy, under award number DE-EE0003239).
The unit comprises a gasifier, gas cleanup, fuel hopper, fuel handling system, diesel genset, and control system. The project focuses on the integration of a biomass gasifier with a commercially available diesel powered genset and aims to distinguish the characteristics of producer gas that may be useful or harmful to the system. The anticipated outcome of the research is a new transportable generation platform capable of displacing fossil fuel use in diesel generators.
The genset, when run on diesel, can generate up to 100 kW of electricity. A target for the genset when run on producer gas is 80 kW. One key benefit of this technology will be a 90 percent or greater potential decrease in greenhouse gas emissions by substituting renewable fuel sources for diesel fuel. The operating efficiency of this prototype system will be compared with the efficiency of the biomass gasification combined heat and power plant already in service on the Morris campus.
The PowerTainer has several potential applications. On farms, the shaft power can be used to run farm machinery, and the producer gas can be used to fuel grain dryers in addition to powering the generator. In disaster areas, wood and debris can be used to fuel the generator and provide electricity or mechanical power. Other potential applications include military and small industry use.