are removed from the anaerobic digesters and fed into nearby biogas engines. The leftover sediment is then transferred to a nearby reservoir, where it is stored for future use as fertilizer. The biogas engines – a Guascor 600 Kwh engine and a Jenbacher 1.2 MWh engine – generate outputs upwards of 650 kW per hour or 250,000 kW a month. The electricity is fed into the NB Power Grid where it can power upwards of 300 homes, while generating approximately 4.5 million BTUs, which is used to heat an on-site farmhouse, the anaerobic di-gesters, hot water tanks, the shop and the dairy barn through the use of an in-floor hydronics system installed underneath the cement floor. “We have lots of extra heat in the summer but not a lot of extra heat in the winter,” Shiell explains. “This is because it takes all the heat to heat the digesters in the winter.” Martin Machinery out of Missouri as-sembled both containerized generation systems. Complete Senergy works with them to assemble custom units that meet the CSA Biogas code required by New Brunswick and Nova Scotia. Complete Senergy Systems also manufactured the mixers, hydronic heater and feed pumps. BIOSOLIDS come at a cost of approximately $1,000 per unit. “They work really well to keep the birds out,” Shiell says. TIPPING FEES Since the amount that is paid per kilo-watt of electricity varies from province to province, this type of operation is typically more worthwhile in areas where higher per kilowatt rates exist. “We only make 10 cents per kilowatt, so 50 per cent of the revenues from this facility come from tipping fees – so Mc-Cain pays per ton to drop off material here, for example,” Shiell explains. Although the paid kilowatt rate in New Brunswick isn’t as high as in prov-inces such as Nova Scotia or Ontario, between electricity generation, tipping fees, operations using the excess heat in the summer and the future pelletizing of fertilizer, Laforge stands to have a bright future in the biowaste business. • The biosolids generated in the electricity generating process are spread out over 1,500 acres of land. “You apply about 2,000 gallons per acre,” Shiell explains. “We take about two or three months in the spring and pretty much spread it all summer. We’ll stop for a couple months during haying season. Then once the grass has been cut, we’ll put some on afterwards and then we’ll keep spreading until November to get the di-gester down as low as we can because we have nowhere to put it during the winter.” One challenge with producing large amounts of biosolids is that the company has to go upwards of 20 kilometres away from the biogas plant to spread it on land, which can become relatively costly. WILDLIFE CHALLENGES One challenge that the operation has expe-rienced is a problem with birds where the organic waste is being stored. To counter this issue, the company is installing tarp curtain doors to keep them out. They Canadian BIOMASS Hoffmann biomass septoct15.indd 1 19 2015-09-25 8:02 AM
Canadian Biomass September/October 2015: Page 19
