Ontario operates the largest greenhouse footprint in Canada. Norfolk's greenhouse footprint is dominated by ornamental, propagation, and nursery operations running 1–10 acre ranges on propane because Enbridge's natural-gas distribution does not reach much of the rural concession-road footprint.
Ontario operates the largest greenhouse footprint in Canada. This page collects the fuel-use context: industry-scale data, fuel-economics comparisons (propane vs. natural gas vs. biomass vs. heat pumps), CO2 supplementation math and combustion-contamination thresholds, sector-specific propane load profiles (vegetable, floriculture, bedding-plant, nursery and propagation), tank sizing and setback math, equipment-type overviews, the IESO energy-profile study, OMAFRA references, and the RSMP private-outlet threshold relevant to greenhouse propane installations.
Concept: Greenhouse fuel economics — propane vs. NG vs. biomass vs. heat pump (May 2026)
Cost per delivered kWh (May 2026 indicative):
| Fuel |
Energy content |
Assumed efficiency |
$ per delivered kWh |
| Propane (bulk delivered, $0.80/L) |
7.03 kWh/L |
85% (modern condensing) |
~13.4 ¢/kWh delivered |
| Natural gas (bulk industrial, $0.20/m³) |
10.4 kWh/m³ |
90% |
~2.1 ¢/kWh delivered |
| Wood chip biomass ($120/tonne, ~3,500 kWh/tonne green) |
— |
75% |
~4.6 ¢/kWh delivered |
| Heat pump (COP 2.5) at OEB off-peak RPP 9.8¢/kWh (effective Nov. 1, 2025) |
1 kWh in → 2.5 kWh out |
— |
~3.9 ¢/kWh delivered |
Caveats. NG reference is industrial Enbridge tariff; ornamental/floriculture customers without NG access cannot capture this rate. Heat pump real-world COP at −20°C will drop below 2.5, raising delivered cost. The 9.8 ¢/kWh OEB off-peak RPP rate is the residential benchmark — commercial Class A/B industrial rates differ and require utility-specific quoting.
When does fuel switching pencil out?
For a 2-acre Norfolk ornamental operator burning ~500,000 L propane/year at $0.80/L (total fuel cost ~$400,000/year):
- CHP retrofit: Not viable without natural gas service.
- Wood-chip biomass boiler ($800,000–$1,500,000 installed for a 4 MMBTU/hr system): displaces 70–80% of propane heat. Annual fuel saving ~$200,000–$280,000. Simple payback 4–8 years if chip supply is secured within 50 km.
- Air-source heat pump retrofit: Not yet economic at Ontario greenhouse winter design temperatures. The University of Guelph / AAFC net-zero greenhouse strawberry pilot funded by the Weston Family Foundation Homegrown Innovation Challenge (June 2025) remains pre-commercial.
- Geothermal hybrid: Capital >$2M for 2 acres; pilots at Niagara College and Vineland Research show 30–50% heating displacement.
Switching-economics thresholds.
- Sustainably below $0.50/L delivered propane → biomass payback extends beyond 10 years; existing propane likely wins.
- Sustainably above $1.10/L delivered propane → biomass payback compresses below 4 years; switching pencils.
- Operations <100,000 L/yr propane consumption → fuel switching is not economic under any current scenario. Focus capital on envelope upgrades (energy curtains, double poly, perimeter insulation) and combustion tuning instead.
Funding programs as of May 2026.
- AgriInnovate (AAFC). Active. Repayable contributions up to $5M for commercialization of clean agtech, including greenhouse heating systems.
- Agricultural Clean Technology Program (AAFC) — Adoption Stream and Research & Innovation Stream. Active. Adoption Stream supports purchase and installation of commercial clean tech (heat recovery, biomass, solar thermal). Application windows can pause; confirm status at agriculture.canada.ca.
- Sustainable Canadian Agricultural Partnership (Sustainable CAP, 2023–2028). Active. Ontario delivery through OMAFRA programs (Resilient Agricultural Landscape Program; Producer-Tier funding for energy efficiency assessments).
- Enbridge Gas Energy Conservation Program. Up to $0.20/m³ NG saved, capped at $250,000 — accessible only to natural-gas customers, not propane.
Watch-point — pre-commercial heat pumps. Watch the University of Guelph / AAFC net-zero greenhouse strawberry project funded by the Weston Family Foundation in 2025 — the Canadian proof-of-concept for displacing fossil heat in commercial greenhouses with heat pumps.
Cross-references: op-ag-propane-price-benchmark-2026-05, (unpublished reference), (unpublished reference), (unpublished reference).
Sources: OMAFRA factsheets on greenhouse energy (Khosla & Spieser); IESO Greenhouse Energy Profile Study (Posterity Group, Sept. 27, 2019); Enbridge Gas Energy Conservation Program; AAFC AgriInnovate and Agricultural Clean Technology Program documentation; OEB Regulated Price Plan rate update effective November 1, 2025; GlobalPetrolPrices.com Canada LPG dataset (April 27, 2026 update).
Concept: Ontario greenhouse industry snapshot (2021–2024)
Ontario farms reported 204.2 million sq. ft. of greenhouse area in 2021 — approximately 4,688 acres — up 27.8% from 159.8 million sq. ft. in 2016 (StatCan Table 32-10-0036-01, 2021 Census of Agriculture; StatCan "Ontario is an agricultural powerhouse," June 15, 2022). Ontario accounts for 61.8% of Canada's total greenhouse area.
Segment breakdown (2021 Census + OGVG 2024):
| Segment |
Approximate Ontario acres (2021–2024) |
Geographic concentration |
| Greenhouse vegetable (TOV, cucumber, pepper) |
~3,800–4,300 |
Essex (Leamington/Kingsville), Chatham-Kent, Niagara |
| Floriculture (cut flowers, potted) |
~700 |
Niagara, Norfolk, Haldimand, Wellington |
| Bedding plants / propagation |
~300 |
Norfolk, Wellington, Perth, Waterloo, Oxford |
| Nursery (containerized, propagation) |
~150 |
Norfolk, Niagara, Waterdown corridor |
| Cannabis (licensed greenhouse) |
~200 (down from ~400 peak) |
Leamington, Niagara, Eastern Ontario |
Fruits and vegetables made up 74.6% of Ontario's 2021 greenhouse area (~152 million sq. ft.). OGVG reported more than 4,300 acres under licence as of August 2024 (OGVG/Blue Book release, Aug. 6, 2024). The Grower's January 2024 industry summary: peppers 1,440 ac, cucumbers 1,098 ac, tomatoes 1,065 ac, strawberries ~400 ac, lettuce ~200 ac.
Geographic distribution. Essex County (Leamington-Kingsville) hosts the overwhelming majority of vegetable acreage. Outside Essex, Norfolk County hosts the highest number of farms in Ontario generally, with a concentrated floriculture/nursery/propagation cluster around Simcoe, Delhi, Waterford, and Vittoria (Norfolk Ag By the Numbers, OMAFRA 2018). Norfolk's greenhouse footprint is dominated by ornamental, propagation, and nursery operations running 1–10 acre ranges on propane because Enbridge's natural-gas distribution does not reach much of the rural concession-road footprint.
Trend lines. 2016 → 2021 saw 27.8% area growth driven by vegetable expansion in Leamington-Kingsville-Chatham-Kent and by cannabis conversion (post-2018). OGVG reported ~6%/yr growth over the decade to 2024, trending to ~5% going forward. Chatham-Kent's new development charges have cooled new vegetable builds. Cannabis acreage peaked 2019–2020 and has retraced; some former cannabis greenhouses converted to strawberries.
Sources: Statistics Canada Table 32-10-0036-01 (2021 Census of Agriculture); StatCan The Daily, "Ontario is an agricultural powerhouse," June 15, 2022; Ontario Greenhouse Vegetable Growers (OGVG) Blue Book release, Aug. 6, 2024; The Grower (OFVGA) industry summary, January 2024; OMAFRA Norfolk Ag By the Numbers (2018).
Reference: IESO Greenhouse Energy Profile Study (Posterity Group, September 27, 2019)
The primary published study of Ontario greenhouse energy use — confirms NG dominance, quantifies electricity use, and provides the cannabis greenhouse intensity figures used in industry comparison.
Document: IESO Greenhouse Energy Profile Study.
Author: Posterity Group (for the Independent Electricity System Operator).
Date: September 27, 2019.
Key facts cited.
- Natural gas is the dominant heating fuel in Ontario greenhouses by area; electricity plays a supporting role for lighting and CHP electrical output.
- Cannabis greenhouse CHP electrical output: 50.81 kWh/sq.ft./yr — approximately 10× vegetable greenhouse intensity.
- Licensed indoor cannabis still higher: 94.07 kWh/sq.ft./yr.
- Vegetable greenhouse baseline electricity and combined-energy figures support the Ecostrat 250,000 m³ NG/acre/yr benchmark used elsewhere.
What this study does NOT cover. Per-segment propane consumption figures are extrapolated from the Ecostrat NG benchmark and OMAFRA CO2 supplementation rates — not from this study.
Related entries: (unpublished reference), (unpublished reference), op-greenhouse-fuel-economics-vs-alternatives.
Reference: OMAFRA Publication 370 — Guide to Greenhouse Floriculture Production (November 4, 2022)
The primary Ontario production reference for greenhouse floriculture — covers crop scheduling, growing media, environmental control, equipment, and energy.
Document: OMAFRA Publication 370, Guide to Greenhouse Floriculture Production.
Date: November 4, 2022.
Related entries: (unpublished reference), (unpublished reference), (unpublished reference), (unpublished reference).
Reference: OMAFRA Factsheet 290/27 — Supplemental Carbon Dioxide in Greenhouses (updated July 23, 2025)
The canonical Ontario citation for greenhouse CO2 enrichment math, target concentrations by crop, and propane combustion contamination thresholds.
Document: OMAFRA Factsheet 290/27, Supplemental Carbon Dioxide in Greenhouses.
ISSN: 1198-712X.
Authors: Blom, Straver, Ingratta, Khosla & Brown.
Date history. Originally published December 2002; migrated to ontario.ca July 8, 2022; most recently updated July 23, 2025.
Key facts cited from this factsheet.
- CO2 yield: "1 m³ of natural gas provides about (1.8 kg) 1,000 L of CO2 when combusted and 1.4 L of water"; "1 m³ of natural gas = 0.75 L of kerosene = 1.0 L of propane for an equivalent amount of CO2 produced." Therefore ~1.8 kg CO2 per L propane combusted.
- Target concentrations: 1,000 ppm general daytime; 800–1,000 ppm seedlings and lettuce; 500–800 ppm African violets and some Gerbera; 1,000–1,300 ppm saturation point most crops under ideal conditions.
- Combustion contaminants: Ethylene at 0.05 ppm causes documented crop damage (premature senescence, flower shatter, bud abortion); propylene specifically associated with propane; >50 ppm CO in flue gases indicates damaging ethylene levels; low-NOx burner mandatory for flue-gas-in-canopy; sulphur ≤0.02% by weight.
Related entries: (unpublished reference), (unpublished reference), (unpublished reference).
Companion OMAFRA references. (unpublished reference) for floriculture production guidance; OMAFRA Using Biomass for Heating Greenhouses in Ontario (Khosla & Spieser) for biomass switching context.
Concept: Greenhouse bedding-plant propane load profile (seasonal Feb–early Jun)
Bedding-plant ranges typically run February through early June with reduced winter idle — the seasonal curve is flipped from year-round ornamental operations. Annual consumption is concentrated into a 12–14 week window.
Annual consumption per acre. 40,000–80,000 L/yr/ac, depending on early-spring scheduling and night setback.
Worked example — 4-acre Wellington / Perth bedding-plant operation:
- Seasonal consumption: 160,000–320,000 L over the Feb–Apr 12-week peak.
- Weekly peak: 20,000–30,000 L during the March crunch.
- Tank configuration: typically two 1,000 USWG (~3,785 L) for small operations up to one 30,000 USWG for larger ranges. Pre-positioning in January is standard — empty tanks in February cannot be refilled fast enough to meet the ramp.
CO2 enrichment. Less common in bedding-plant production than in year-round ornamental or vegetable production (per OMAFRA Publication 370 Guide to Greenhouse Floriculture Production, November 4, 2022 — see (unpublished reference)). Where used, propane CO2 generators target 800–1,000 ppm. See (unpublished reference).
Pre-positioning logic. Because the consumption curve is February-loaded, top off storage in January rather than November. The supplier's truck cadence in March must match weekly peak draw or the operator runs short during the growing window.
Cross-references: (unpublished reference) (flipped curve), (unpublished reference), (unpublished reference).
Sources: OMAFRA Publication 370 Guide to Greenhouse Floriculture Production (November 4, 2022); OMAFRA Supplemental Carbon Dioxide in Greenhouses (Factsheet 290/27, updated July 23, 2025).
Concept: Greenhouse bulk propane tank sizing and setbacks
Tank sizing for greenhouse installations is driven by burner load and minimum-inventory-floor logic (see (unpublished reference) for pre-positioning calendar), not by greenhouse acreage alone.
Common greenhouse tank sizes: 1,000 USWG (~3,785 L), 2,000 USWG, 4,000 USWG, 10,000 USWG, 18,000 USWG, 30,000 USWG.
Typical sizing by operation:
| Operation |
Typical tank set |
Notes |
| 1-ac propagation / nursery |
1,000–4,000 USWG single tank |
A single 4,000 USWG sits at the ECCC E2 plan threshold (see below). |
| 2-ac bedding-plant seasonal |
Two 1,000 USWG up to one 30,000 USWG |
Pre-position in January for Feb–Apr peak. |
| 2-ac year-round ornamental (Norfolk poinsettia/mum) |
Manifolded pair of 30,000 USWG (~225,000 L working storage) |
~10 weeks January peak draw between deliveries; supports continuous winter draw without vaporizer freeze-off at most loads. |
| 5-ac+ vegetable on propane (rare) |
Multiple manifolded 30,000 USWG with external vaporizer |
See (unpublished reference). |
Aboveground vs. underground. Aboveground installations are standard for greenhouses. Underground is rare (higher capital, more complex inspection per CSA B149.2).
Vaporizers. Required when continuous draw exceeds the natural vaporization capacity of the tank surface area. Practical rule: any sustained draw over ~1.5 M BTU/hr per 30,000 USWG tank at −10°C calls for a vaporizer or additional tank capacity. Most year-round ornamental loads at 2 acres or less stay under this with a manifolded 2× 30,000 USWG set; vegetable operations almost always need an external vaporizer.
TSSA setbacks (CSA B149.2-20 Table 5.2, adopted via O. Reg. 211/01 — see (unpublished reference), (unpublished reference)):
- 30,000 USWG (113,500 L) tank: 50 ft (15 m) minimum setback from buildings, property lines, and ignition sources.
- Smaller bulk tanks (1,000–4,000 USWG): 10–25 ft setback depending on tank size.
- PRV discharge, hose connection point, transfer-pump location, and fencing requirements specified in CSA B149.2 Section 6.
TSSA Director's Order FS-271-24. All tanks must be ≥250 psig MAWP as of October 1, 2025 — older 200-psig tanks are non-compliant (see (unpublished reference)). Greenhouse operators with pre-1995 tanks should have replaced them before the 2025 fall season.
E2 plan threshold. Federal Environmental Emergencies Regulations, 2019 (SOR/2019-51) trigger at 4.5 tonnes propane on-site (~9,300 L liquid). A single 4,000 USWG tank is at the threshold; multi-tank greenhouse installations cross it well clear. See (unpublished reference).
RSMP threshold. RSMP under O. Reg. 211/01 is generally not triggered for typical own-use greenhouse heating installations under ~19,000 L; see (unpublished reference) for the case-by-case TSSA determination.
Sources: CSA B149.2-20 Table 5.2 (adopted by O. Reg. 211/01); TSSA Director's Order FS-271-24 (August 8, 2024); Environmental Emergencies Regulations, 2019, SOR/2019-51.
Concept: Greenhouse floriculture and ornamental propane load profile (Norfolk-style)
The dominant propane-served greenhouse segment: Norfolk-style ornamental, floriculture, and cut-flower operations running 1–10 acre ranges on double-poly or glass-double-poly hybrid envelopes, outside the Enbridge NG distribution footprint.
Annual consumption per acre. Double-poly envelopes have roughly half the heat loss of glass; OMAFRA Supplemental Carbon Dioxide in Greenhouses (Factsheet 290/27, updated July 23, 2025) notes double-poly CO2 supplementation requirements are about half of glass on a per-hour basis. Applying the envelope ratio: 125,000–185,000 L propane per acre per year for a year-round ornamental operation.
Worked example — 2-acre Norfolk poinsettia / spring-mum operation:
- Annual consumption: 250,000–370,000 L/yr.
- January peak: 15,000–25,000 L/wk.
- Tank configuration: two 30,000 USWG (≈113,500 L) aboveground tanks in a manifolded system. Supports continuous winter draw without vaporizer freeze-off limits at most operations; vaporizer sometimes required at the high end of the range or in deep cold.
CO2 enrichment. Most Norfolk floriculture operators run dedicated propane CO2 generators targeting 800–1,000 ppm daytime (OMAFRA: "a lower level (800–1,000 ppm) is recommended for raising seedlings (tomatoes, cucumbers and peppers) as well as for lettuce production"; 1,000 ppm general recommendation when vents are closed). CO2 enrichment adds ~10–15% to fuel consumption depending on venting strategy. See (unpublished reference) for combustion-physics detail.
Season profile. Nov–Feb = 65–70% of annual fuel; peak weekly draw mid-January. Mar–Apr bedding-plant shoulder peak. May–Sept minimal. See (unpublished reference).
Equipment: Hot-water boilers with under-bench, perimeter, and crop-canopy distribution are the dominant configuration in larger floriculture operations because they integrate with thermal storage tanks for daytime CO2 capture. See (unpublished reference).
Sources: OMAFRA Supplemental Carbon Dioxide in Greenhouses (Factsheet 290/27, updated July 23, 2025); OMAFRA Publication 370 Guide to Greenhouse Floriculture Production (November 4, 2022); Ecostrat Ontario cap-and-trade greenhouse modelling (2016–2017).
Concept: Greenhouse nursery and propagation propane load profile
Smaller heat loads than year-round floriculture, often a propagation house feeding outdoor nursery beds. Common in Norfolk and the Waterdown corridor.
Annual consumption per acre. 20,000–60,000 L/yr/ac, depending on year-round vs. seasonal use.
Worked example — 1-acre Norfolk propagation house:
- Annual consumption: 30,000–50,000 L/yr.
- Weekly peak: 5,000–8,000 L/wk.
- Tank configuration: 1,000–4,000 USWG are typical at this scale. A single 4,000 USWG tank sits at the ECCC E2 plan threshold of 4.5 tonnes (~9,300 L) propane on-site — see (unpublished reference).
Equipment. Often direct-fired unit heaters (vented to keep combustion gases out of the canopy) rather than the hot-water boiler architecture used in larger floriculture and vegetable operations. Infrared tube heaters appear in propagation tunnels where spot heat is required. See (unpublished reference).
CO2 enrichment. Less common at propagation scale than at year-round ornamental scale; where used, propane CO2 generators are typical (Reznor, Roberts Gordon, Priva — see equipment entry).
Cross-references: (unpublished reference), (unpublished reference) (segment context — nursery ~150 ac province-wide).
Sources: OMAFRA Publication 370 Guide to Greenhouse Floriculture Production (November 4, 2022); OMAFRA Supplemental Carbon Dioxide in Greenhouses (Factsheet 290/27).
Concept: Greenhouse propane CO2 enrichment math and combustion contamination thresholds
CO2 yield. Verbatim from OMAFRA: "1 m³ of natural gas provides about (1.8 kg) 1,000 L of CO2 when combusted and 1.4 L of water" and "1 m³ of natural gas = 0.75 L of kerosene = 1.0 L of propane for an equivalent amount of CO2 produced." That is: ~1.8 kg CO2 per litre of propane combusted; ~1.8 kg CO2 per m³ of natural gas.
On an energy basis, propane delivers slightly more CO2 per MJ (advantageous when CO2 is the goal). The trade-off is moisture: propane combustion produces somewhat less water vapour per kg CO2 than natural gas — useful in fall/spring when canopy humidity management is already at the limit.
Target CO2 concentrations (OMAFRA recommendations). Ambient is ~420 ppm in 2026 (rising).
- General recommendation: "carbon dioxide supplementation of 1,000 ppm during the day when vents are closed is recommended."
- Saturation point most crops: "about 1,000–1,300 ppm under ideal circumstances."
- Seedlings (tomatoes, cucumbers, peppers) and lettuce: 800–1,000 ppm.
- African violets and some Gerbera varieties: 500–800 ppm.
Combustion contaminants — operator-grade detail (OMAFRA verbatim).
- "Ethylene at 0.05 ppm and propylene at higher levels can cause premature senescence on tomato and cucumber plants, induce sleepiness in carnations, create flower shatter of geraniums, promote excessive side shoot development, prevent normal flower initiation, and flower bud abortion in chrysanthemums and poinsettia. Ethylene is often produced as a result of incomplete combustion, while propylene is usually associated with the use of propane. Leaky propane supply lines have created serious financial damage to growers in the past."
- "Levels exceeding 50 ppm CO in the flue gases are an indication of the presence of ethylene at levels capable of causing crop damage."
- "Boilers equipped with low NOx burners must be used for flue gas utilisation as a CO2 source."
- "Sulphur levels in the fuel should not exceed 0.02% by weight."
Operator implication. Propane is a clean CO2 source only if the burner is tuned, supply lines are leak-free, and HD-5 (≥90% propane) specification fuel is delivered (see (unpublished reference)). Operators using propane CO2 generators should commission annual combustion tuning and CO and ethylene monitoring.
Equipment. Dedicated CO2 generators (Reznor, Roberts Gordon, Priva, Johnson Gas Appliance) sized 20,000–60,000 BTU/hr per unit, covering ~4,800 sq. ft. each, are typical in Norfolk floriculture. Larger operations use flue-gas condensers on hot-water boilers with daytime CO2 storage tanks. See (unpublished reference).
Cross-references: (unpublished reference), (unpublished reference), (unpublished reference), (unpublished reference).
Sources: OMAFRA Factsheet 290/27 Supplemental Carbon Dioxide in Greenhouses (Blom, Straver, Ingratta, Khosla & Brown; originally December 2002; migrated to ontario.ca July 8, 2022; most recently updated July 23, 2025); John Bartok, Greenhouse Management, January 14, 2025.
Concept: Greenhouse propane equipment types (boilers, unit heaters, CO2 generators)
Three heater categories cover the Ontario propane-served greenhouse installed base, plus dedicated CO2 generators where flue-gas-into-canopy is not viable.
Hot-water boilers. Dominant configuration in larger floriculture and vegetable operations. Under-bench, perimeter, and crop-canopy distribution. Integrates with thermal storage tanks to allow daytime CO2 capture from flue gas through a condenser. The architecture that supports CO2 enrichment from boiler combustion (vs. dedicated generators).
Direct-fired unit heaters. Common in smaller, retrofit, and bedding-plant ranges. Vented unit heaters keep combustion gases out of the canopy; unvented are still used in some bedding-plant ranges but risk ethylene/CO problems at the levels OMAFRA flags as crop-damaging (see (unpublished reference)).
Infrared tube heaters. Niche use; effective in propagation tunnels where spot heat is required. Not a primary heat source for year-round operations.
Dedicated CO2 generators. Where flue-gas-into-canopy is not appropriate (older boiler without low-NOx burner, unvented architecture, biomass boiler with unsuitable flue gas), operators install dedicated propane CO2 generators. Common OEM brands: Reznor, Roberts Gordon, Priva, Johnson Gas Appliance. Sizing typically 20,000–60,000 BTU/hr per unit, covering ~4,800 sq. ft. each. Most Norfolk floriculture operators target 800–1,000 ppm daytime.
Low-NOx burner requirement for flue-gas-in-canopy. OMAFRA verbatim: "Boilers equipped with low NOx burners must be used for flue gas utilisation as a CO2 source." Operators retrofitting boilers for CO2 capture must commission annual combustion tuning.
Biomass boilers (parallel infrastructure). Larger Essex/Kent operations adopting wood-chip and biomass-pellet boilers (often paired with flue-gas scrubbing for CO2 recovery) — see op-greenhouse-fuel-economics-vs-alternatives for the switching economics. Common in vegetable operations >300,000 L/yr propane displacement target.
CHP (combined heat and power). Natural-gas reciprocating engines more common in lit vegetable operations where the operator can monetize electricity sales to the IESO and recover both heat and CO2. Not a propane play in practice.
Cross-references: (unpublished reference), (unpublished reference), (unpublished reference), (unpublished reference).
Sources: OMAFRA Publication 370 Guide to Greenhouse Floriculture Production (November 4, 2022); OMAFRA Supplemental Carbon Dioxide in Greenhouses (Factsheet 290/27, updated July 23, 2025); OMAFRA Using Biomass for Heating Greenhouses in Ontario (Khosla & Spieser); IESO Greenhouse Energy Profile Study by Posterity Group (September 27, 2019).
Concept: Greenhouse vegetable propane load profile (TOV, cucumber, pepper)
Energy-intensity benchmark. Ecostrat's Ontario cap-and-trade compliance modelling (2016–2017 vintage) cited 250,000 m³ natural gas per acre per year as the Ontario vegetable greenhouse benchmark. Energy-equivalent on propane (at 25.3 MJ/L propane HHV vs. 37.5 MJ/m³ NG HHV): ~370,000 L/ac/yr propane.
SW Ontario applicability. Vegetable greenhouses on propane are uncommon — most Ontario vegetable acreage (peppers 1,440 ac, cucumbers 1,098 ac, tomatoes 1,065 ac per The Grower, January 2024) is in NG-served Essex/Kent/Niagara (see (unpublished reference)). Where propane-fired vegetable operations exist (independent 1–3 acre tomato or specialty pepper operations in Oxford or Perth), expect:
- ~200,000–400,000 L/ac/yr.
- 30,000+ L/wk peak winter draw.
- A 5-ac operation: ~1.5–1.9 M L/yr.
Tank sizing. Minimum two 30,000 USWG manifolded with vaporizer for continuous high-BTU draw. Vapor-draw threshold roughly 1.5 M BTU/hr per 30,000 USWG at −10°C ambient — vegetable operations exceed this and require external vaporizer. See (unpublished reference).
CO2 enrichment. Vegetable operations typically target 1,000–1,300 ppm CO2 daytime under ideal conditions per OMAFRA Supplemental Carbon Dioxide in Greenhouses (see (unpublished reference)). Propane combustion yields ~1.8 kg CO2/L (see (unpublished reference)). Operators using flue-gas-into-canopy must run low-NOx burners per OMAFRA guidance.
Cross-references: (unpublished reference) (much more common on propane in SW Ontario), (unpublished reference), op-greenhouse-fuel-economics-vs-alternatives.
Sources: Ecostrat Ontario cap-and-trade greenhouse modelling (2016–2017); OMAFRA Supplemental Carbon Dioxide in Greenhouses (Factsheet 290/27, updated July 23, 2025); IESO Greenhouse Energy Profile Study by Posterity Group (Sept. 27, 2019).