ENERGY SYSTEM PROVIDER
As an Integrated System Provider, Phase 3 Renewables will supply all the equipment, materials, and associated services for implementing your biomass energy system.
Phase 3 Renewables can provide a variety of energy conversion systems, for replacement of purchased energy as well as excess energy which can be sold to a local utility or neighboring business. This section covers uses for biogas from anaerobic digestion; please see the gasification tab for energy production from that technology.
Electricity
Pipeline Quality Gas
Compressed Biomethane for Vehicle Fuel
Steam and Hot Water
The most appropriate choices for your operation will be dependent on a number of factors:
- On-farm energy uses and consumption - how much electricity, natural gas and propane do you use? Is your use constant or seasonal? Will your consumption grow in the future?
- Current energy rates - Are you paying more than $0.08 per kilowatt hour for electricity? Are you forced to use propane at >$2.00 per gallon because natural gas is not available?
- Distance from local utility lines - How close is your farm to the substation or natural gas line? Are you served by three-phase or single-phase power lines?
Overview of the process for Energy Systems
Electricity Generation
The process
Electricity can be generated by combusting biogas in a spark-ignited engine or converted dual-fueled diesel engine. The biogas can be used directly if hydrogen sulfide levels are low; otherwise it is necessary to scrub the biogas of H2S and condensed water. There are numerous generator choices on the market, and pricing varies dramatically. Phase 3 Renewables constantly evaluates these choices to provide you with a list of alternatives and a recommendation for your site.
Process Overview - Electricity
System requirements
The turbine and generator you choose, as well as your interconnection to the grid, will depend upon economic and technical factors.
Electrical Interconnection Cost & Feasibility Determination
 |
|
Most systems run parallel with the grid, providing back-up and additional power when the biogas generator is not producing enough energy or is down for maintenance. By interconnecting with the grid, you can sell excess energy. However, it is also possible to run isolated from the grid using stand-alone, prime-mover generators. This may be the best choice if your farm is small, since interconnection costs can be very high and unjustified if you will only have a small amount of excess electricity to sell. Phase 3 Renewables has teamed up with I Power Energy Systems to create such an option - a dual-fueled generator that supplies just the amount of power needed for your operations.
Two I-Power Energy System dual-fuel generators provide 130-140 kW of three phase power to the Geerlings Hillside Farms - Overisel Swine Facility. The proprietary gensets can run on either natural gas or biogas. This saves you money on startup by providing both heat and power while your digester is not yet producing suitable biogas for electricity generation. The gensets also provide 3-phase power, eliminating the need for costly utility line changes. Waste heat is captured to meet digester and farm needs for heating.
Renewable energy production and sales potential
A rough rule of thumb is that for every 3.5 standard cubic feet per minute (scfm) of biogas available, you can make 1 kW of electricity. Another rough rule of thumb is that for every gallon of typical dairy manure, a properly operating digester will generate about 2.5 to 4.5 scfm. So a 1000 cow dairy could generate enough biogas for about 325kW in an engine that is 35-38% efficient. The annual value of this electricity will depend on what you pay and what you can get paid if you sell excess power to the electric utility.
2,419,950 kWh per year, assuming 85% uptime on generator
| $/kWh | $0.04 | $0.06 | $0.08 | $0.10 | $0.12 |
| Annual $ | $96,798 | $145,197 | $193,596 | $241,995 | $290,394 |
The rest of the energy value from the biogas becomes waste heat that is used to keep the digester hot and provide hot air or water elsewhere on the farm. Our Pathways 2 Profit™ model will help you understand your production potential, and our laboratory will test your manure for biogas potential. We can also assess potential co-feed materials that could significantly increase your biogas productivity when combined with manure.
Links to Phase 3 Renewables' projects implementing Electricity Generation
Scenic View Dairy - Fennville I
Geerlings Hillside Farms
Scenic View Dairy - Freeport
Pipeline Quality Gas
The process
Phase 3 Renewables has made upgrading biogas to pipeline quality standards farm-friendly. Our proprietary integrated systems provide an alternative for making money from your manure, incorporating proprietary QuestAir Technologies pressure swing absorption units.
The biogas must be initially cleaned of high levels of H2S, and a portion of the H2O vapor must be condensed from the saturated gas. The biogas then enters the compressor, where operating pressure and gas discharge temperature are controlled to ensure operation above the dew point and avoidance of condensation in the compressor. The biogas is cooled again, condensing additional H2O from the biogas prior to entering the Pressure Swing Absorption (PSA) equipment. Coalescing filters are used in several places to ensure free water and oil is eliminated. The PSA cycles the biogas through a series of adsorbent beds to separate the methane from the CO2, H2S, and H2O vapor, delivering a product gas that meets pipeline quality standards. The separated exhaust gas contains approximately 150-300 BTUs and can be used to fuel a low-BTU boiler for supplemental digester heating or biofiber conditioning. Alternatively, the exhaust gas can be co-fired with another fuel to generate power.
System requirements
Phase 3 Renewables markets two pre-assembled fully integrated Biogas Upgrading skids (BUS). The PHASE 3 BUS A ™ processes between 75-170 scfm of biogas, while the PHASE 3 BUS B ™ processes between 225-350 scfm of biogas. Each of these skids are built to be farm-friendly, easy to operate and maintain, and with low parasitic energy requirements. Since most US pipelines in rural areas operate at above 75 psig, the gas must be compressed. This makes the use of pressure swing absorption highly cost competitive compared to alternative upgrading technologies which require costly chemicals or membrane replacements.
Renewable energy production and sales potential
For a 1,500-head dairy or 40,000 hog spaces:
| 38,533 | Total volume (1,000 cft) of Natural Gas available for Pipeline / year |
| $288,998 | Potential Natural Gas Revenue Stream / year |
| Price Range - Nat gas price/1000cft | Revenue Range / year | ||||
| Low | Modeled | High | Low | Modeled | High |
| $4.000 | $7.500 | $10.500 | $154,132 | $288,998 | $404,597 |
Links to Phase 3 Renewables' projects implementing Pipeline Gas
Vehicle Fuel
The process
Once the biogas has been upgraded to biomethane, it can also be compressed for cost effective use as a vehicle fuel. Phase 3 Renewables supplies a second pre-assembled skid with compression equipment to increase the pressure to 3600 psig. Then the compressed biomethane is stored in a set of cylinders which operate in a cascade fashion to maintain high pressure while dispensing the compressed biomethane into specialized fuel tanks on the vehicle.
System requirements
Vehicles can be configured to run on dual fuel, where 0-90% biomethane is mixed with gasoline or diesel fuel. Alternatively, other engines run on 100% biomethane. New vehicle engines and conversion kits are available for cars, pickups, heavy duty trucks and semis, complete with manufacturer's warranty. Each manufacturer will specify the gas quality required, but normally the minimum is 900 BTU/cubic foot. The fuel tanks are now made of advanced fiber composites which make the tanks lighter than conventional fuel tanks. Because of the lighter tanks, more fuel can be carried on the vehicle, extending the range between fill-ups.
Production potential
The fuel value of compressed biomethane is proportionate to the BTU value:
| FUEL | BTU/GAL | CFT BIOMETHANE | CFT RAW BIOGAS | |
| Gasoline | 124,800 | 131 | 245 | |
| Diesel | 130,400 | 137 | 256 | |
A 2,000-cow dairy could produce enough biogas for over 900 gallons of gasoline or diesel equivalent per day!
Links to Phase 3 Renewables' projects implementing Vehicle Fuel
Steam & Hot Water
The process
Biogas can be used with minimal scrubbing of corrosive
H2S in traditional boilers, often with less than a one day
retrofit. Anywhere that natural gas or propane is
currently used to generate steam or hot water, you could
now use biogas to meet this energy requirement.
System requirements
Most commercial boilers require only minor retrofit in order to allow a greater volume flow rate of low BTU gas to meet total BTU/hr requirements. This typically involves re-drilling the nozzles or a new burner, both of which are much less costly than a new boiler.
Production potential
Steam and hot water can be produced either directly from the combustion of biogas in a boiler or as part of a combined heat and power system. A rough rule of thumb is that for every 100kW of electricity generated, an additional 500,000 BTUs/hour are available as waste heat. If all the biogas were instead used for steam generation, the biogas could support a 900,000 BTU boiler.
Links to Phase 3 Renewables' projects implementing Steam & Hot Water