Table 1 Main results when maximizing different profits for biogas supply network with smaller capacity (1 ± 0.1 MW in average electricity production)
Max PEconomic | Max \( {P}^{Economi{c}^{+ GHG}} \) | Max PSustainability b | |
|---|---|---|---|
Feedstock (t/y) | |||
Corn grain | 7488 | 7488 | 11,820 |
Corn silage | / | / | 14,354 |
Corn stover | 5105 | 5105 | 8059 |
Poultry bedding | 9355 | 9355 | / |
Poultry manure | 2236 | 2236 | 25,505 |
Poultry slurry | / | / | 25,463 |
Total feedstock | 21,949 | 21,949 | 85,200 |
Products | |||
Electricity (MWh/y) | 8386 | 8368 | 23,968 |
Heat (MWh/y) | 5955 | 5955 | 17,378 |
Digestate (23% dry solids, t/y) | 13,353 | 13,399 | 48,749 |
Corn grain (direct product) | 7239 | 7239 | 11,424 |
Water (t/y) | |||
Purchased | 3230 | 3230 | 213 |
Recycled | 11,503 | 11,503 | 46,438 |
Utilities required (MWh/y) | |||
Electricity “recycled” | 531 | 548 | 2092 |
Electricity purchased | 185 | 168 | / |
Heat “recycled” | 1700 | 1700 | 4968 |
Heat source purchased | / | / | / |
Sustainability item ($/y) | |||
Economic profit | − 548,346 | −548,452 | −2,323,475 |
Eco-profit | − 113,681 | 321,269 | 2,802,824 |
Social profit | 77,456 | 77,456 | 230,344 |
Sustainability profit | − 584,572 | − 149,728 | 709,692 |
Economic+GHG profit | −500,291 | − 498,191 | −2,157,453 |
CO2 eq. emissions (t/y)a | − 1807 | − 1890 | − 6241 |
Selected Site | I | I | I, II, III |
Dry matter content (%) | 13 | 13 | 12.06|11.97|11.91 |
Methane content (%) | 56.18 | 56.18 | 55.87|56.36|56.92 |