1. Biogas Preliminary Design Study Yukon Biomass Forum March 16th, Funded by Yukon Energy and Cold Climate Innovation and City of Whitehorse

2. Why are we looking at this project?
To continue to look at renewable energy options
To produce electricity and heat from a waste
To find synergies with integrating Biogas with the current compost systems.
Previous work done: City, ESC, -AECOM, Yukon Energy and CCI, and now YEC, CCI and City

3. Two applications: Boiler (heat) or CHP (heat and electricity)
Biogas: What is it?
Biogas is ~ 60% methane, ~ 40% CO2.
Anaerobic digestion of organic waste
Food waste, paper waste, cooking oils, slaughterhouse wastes, sewage sludge
Two applications: Boiler (heat) or
CHP (heat and electricity)
Compost is the aerobic digestion. Needs oxygen. Anaerobic is without oxygen

4. Incoming Organic Feedstock
Tonnes
50% diversion by 2020 goal
Comes from City of Whitehorse expected organic diversion resident participation, consultant experience and extrapolation of previous studies.
2% population growth
SSO - Source Sorted Organics
ICI - Industrial, Commercial, Institutional
DGW – Dry Garden Waste
FGW - Fresh Garden Waste

5. Technology Selection: Dry digestion, horizontal batch
Single stage, horizontal batch dry digestion at mesophilic temperatures (55C)
Uses a front end loader. No pumps. No huge water requirements or dewatering. Simple to operate, affordable, uses or discharges no water requires no front end contaminant removal. Less noise and odor nuissance.
Digestion takes around days generally
Composting happens afterward. Some systems have a pasteurization step which eliminates the need for composting. Composting is still needed to get up to 70C to eliminate weed seeds and pathenogens.
25% solids for dry digestion. WH feedstock never less than 24%
Used at Harvest Power in Richmond BC and University of Wisconsin
Mesophilic is more stable and uses less energy than thermophilic. More mesophilic microorganisms available.
Technology chosen by feedstock and on-site conditions.
Simple to operate, does not need water, can handle contaminants,
less energy needs, more stable process

6. Estimated biogas production for 2016
Tonnes
Storage is for 3-10 hrs about 1,200 kWhe
SSO - Source Sorted Organics
ICI - Industrial, Commercial, Institutional
DGW – Dead Garden Waste
FGW – Fresh Garden Waste

7. Biogas System

8. First
100kW unit
1.7 GWhe current from wind at 30% capacity factor

9. Biogas plant configuration with Boiler
One 500hp boiler
Heat loop to local buildings (compost and KBL Building) or theoretical greenhouse.
Greenhouse is designed at 486m2, which would be approximately 2% of Whitehorse’s demand for vegetables.

12. Economics: CHP Capital Expenditures: $7.1M
Operational Expenditures: $250,000
Lifecycle Cost of Energy (LCOE) Sensitivity Analysis
Gate Fees $/Tonne
Capital Subsidy
LCOE ($/kWhe) 38 0%
$0.64 36
70%
$0.21 45
$0.58
50%
$0.26 50
$0.53
40%
$0.28

13. Economics: Boiler Capital Expenditures: $6.1M
Operational Expenditures: $247,000
LCOE Sensitivity Analysis
GATE FEES $/TONNE
CAPITAL SUBSIDY
LCOE ($/GJ) 38 0%
$63.0
70%
$23.5 45
$56.4
60%
$22.5 50
$51.7
40%
$29.1

14. Peak heat generation Dec - Feb
Heating
Greenhouse
CAPEX: $167,625
OPEX per year: $79,485
Greenhouse
Heat required Dec - Feb
CHP
Peak heat generation Dec - Feb
Boiler
167 kWth
41 kWth
118 kWth

15. Conclusions Waste seasonality can be an issue
Greenhouse heat demand is highest in the winter, when production is low.
Project is only economic with significant capital subsidy
CHP scenario economics fare better than the heat only project
Not enough demand for heat only
Could be other values/benefits of a project like this beyond an energy project
The highest energy availability from an AD plant occurs during the summer months. Input tonnages are higher in summer. Which leads to higher biogas production. In the summer, internal energy consumption is lower due to outdoor temperatures.
Biogas produces higher energy in the summer and less in the winter. Greenhouses need more energy in the winter, much like any other energy consumer
Imbalance of energy production and generation for this kind of project

16. Next steps
Could look into landfill gas capture to boost energy production
Look at project economics of an Integrated Composting and Biogas facility
Reduction in composting time after Biogas could save operational costs

17. Thanks
City of Whitehorse: Miles Hume, Clayton Peacock, Dan Jordan, Shannon Clohosey, David Albisser, Jackie Taylor, Wayne Tuck
Cold Climate Innovation: Stephen Mooney, Ziad Sahid, Aaron Roberge
Garret Gillespie