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, named operators on the public record, and the RSMP private-outlet threshold relevant to greenhouse propane installations. Each section absorbs a previously-standalone card verbatim. Section anchors mirror the prior slugs.

Concept: Greenhouse fuel economics — propane vs. NG vs. biomass vs. heat pump (May 2026)

Confidence: Estimated — indicative cost figures based on industry benchmarks; not a published official comparison.

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, op-greenhouse-floriculture-ornamental-propane-load-profile, op-greenhouse-vegetable-propane-load-profile, reference-ieso-greenhouse-energy-profile-study-2019.

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)

Confidence: Verified for province-level totals (StatCan); Inferred for SW-Ontario-specific propane-vs-NG split (no published county fuel-mix table).

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 — Richard Lee, OGVG executive director: "Southwestern Ontario is the critical mass for greenhouse vegetable production ... we experience the most light levels throughout the year, which makes our area the optimum location to grow food" (The Packer, 2024). 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 — Lee (The Grower, 2024): development fees "will cost a greenhouse grower $179,000 per acre in 2024 ... will gradually escalate until 2029 at which time it will cost $366,000 per acre before a shovel enters the ground." Cannabis acreage peaked 2019–2020 and has retraced; some former cannabis greenhouses converted to strawberries.

Scope note for B&J relevance. The propane-served greenhouse customer base in B&J's SW Ontario service area sits outside the Leamington-Kingsville NG cluster — Norfolk, Oxford, Brant, Wellington, Waterloo, Perth, Huron, Middlesex, Elgin, Haldimand. These are predominantly floriculture, bedding-plant, nursery, and propagation operations, not vegetable greenhouses.

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; The Packer interview with Richard Lee, 2024; OMAFRA Norfolk Ag By the Numbers (2018).

Reference: IESO Greenhouse Energy Profile Study (Posterity Group, September 27, 2019)

Confidence: Verified.

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.

Use-cases. Cite this study when:

• Establishing that natural gas dominates Ontario greenhouse heating by area (and propane is the alternative outside the Enbridge footprint).
• Discussing cannabis greenhouse energy intensity for any comparative analysis.
• Framing the CHP economics of NG-served vegetable operations (relevant background context even though propane-served operations cannot replicate this play).

What this study does NOT cover. Standalone propane-fired licensed cannabis facilities do not publish fuel data; the IESO study captures cannabis energy only at the electricity-CHP boundary. Per-segment propane consumption figures are extrapolated from the Ecostrat NG benchmark and OMAFRA CO2 supplementation rates — not from this study.

Related entries: op-ontario-greenhouse-industry-snapshot-2024, op-greenhouse-vegetable-propane-load-profile, op-greenhouse-fuel-economics-vs-alternatives.

Reference: Named SW Ontario greenhouse operators (publicly profiled, 2026)

Confidence: Verified (publicly named in trade press); operator-level fuel data is not disclosed.

Greenhouse operators publicly profiled in Ontario trade press, by segment and geography. Use as named references when fact-checking SW Ontario greenhouse content or building city-page operator examples.

Norfolk-area propagation and nursery:

• Sheridan Nurseries — Norfolk-area propagation; profiled in Greenhouse Canada.

Niagara floriculture (reference for SW Ontario comparison):

• Linwell Gardens — Niagara floriculture.
• Pioneer Flower Farms — Niagara floriculture.

Greenhouse structures supplier with Norfolk customer base:

• Westbrook Systems — St. Catharines structures supplier; customers in Norfolk and across SW Ontario.

Eastern Ontario bedding-plant reference:

• Burt's Greenhouses — Kingston; bedding plants.

West-coast Ontario nursery/greenhouse:

• Huron Ridge Acres — Zurich; nursery and greenhouse operation.

Vegetable cluster (outside scope but referenced for context): Essex County (Leamington/Kingsville) hosts the overwhelming majority of vegetable acreage; the named operators above are propane-served or propagation/nursery-focused, not Essex vegetable operators.

Use convention. For any SW Ontario greenhouse content (article, city page, KB cross-reference), prefer named real operators from this list over generic "a Norfolk floriculture operator." When an operator is named, ensure the trade-press citation is intact — these are public-record facts, not B&J customer disclosures.

Cross-references: op-ontario-greenhouse-industry-snapshot-2024, op-greenhouse-floriculture-ornamental-propane-load-profile, reference-ontario-greenhouse-industry-voices.

Sources: Greenhouse Canada (monthly trade press); The Grower (OFVGA); operator websites and OMAFRA county-profile materials.

Reference: OMAFRA Publication 370 — Guide to Greenhouse Floriculture Production (November 4, 2022)

Confidence: Verified.

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.

Use-cases. Cite this publication when answering operator questions about:

• Floriculture crop scheduling and the role of CO2 enrichment in different production windows.
• Heating equipment selection for floriculture (hot-water boiler vs. direct-fired unit heater).
• Bedding-plant production scheduling and the February ramp.
• Energy and combustion best practices specific to floriculture.

Why this matters for B&J's customer base. The propane-served greenhouse segments in SW Ontario (Norfolk floriculture, Wellington/Perth bedding plant) are exactly the audience Publication 370 addresses. Vegetable production guidance lives in separate OGVG and OMAFRA vegetable resources.

Related entries: op-greenhouse-floriculture-ornamental-propane-load-profile, op-greenhouse-bedding-plant-propane-load-profile, op-greenhouse-propane-equipment-types, reference-omafra-supplemental-co2-greenhouses.

Reference: OMAFRA Factsheet 290/27 — Supplemental Carbon Dioxide in Greenhouses (updated July 23, 2025)

Confidence: Verified.

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.

Operator use-cases. This is the single Ontario primary source for any greenhouse-CO2-enrichment or propane-clean-combustion conversation. Cite this factsheet when answering operator questions about:

• Whether propane is a clean CO2 source.
• Why leaky propane supply lines damaged crops historically.
• What ppm targets to set for which crop.
• Why HD-5 (≥90% propane) specification fuel matters for CO2 generators.

Related entries: op-greenhouse-propane-co2-enrichment-math, op-greenhouse-propane-equipment-types, op-hd5-propane-spec-combustion-quality.

Companion OMAFRA references. reference-omafra-publication-370-greenhouse-floriculture for floriculture production guidance; OMAFRA Using Biomass for Heating Greenhouses in Ontario (Khosla & Spieser) for biomass switching context.

Reference: Ontario greenhouse industry voices, ministry specialists, and trade press

Confidence: Verified.

Named voices and outlets used as primary sources for Ontario greenhouse articles, KB entries, and customer-facing pages.

Ontario Greenhouse Vegetable Growers (OGVG):

• Richard Lee — Executive Director. Most-quoted Ontario voice on greenhouse vegetable industry, geography, and development-charge issues. Representative quote (The Packer, 2024): "Southwestern Ontario is the critical mass for greenhouse vegetable production ... we experience the most light levels throughout the year, which makes our area the optimum location to grow food."

OMAFRA / OMAFA greenhouse specialists (note: ministry rebranded OMAFRA → OMAFA — Ontario Ministry of Agriculture, Food and Agribusiness — in 2024):

• Shalin Khosla — Greenhouse Vegetable Specialist, Harrow. Co-author of OMAFRA's biomass and CO2 factsheets.
• Helmut Spieser — Engineer, Field Crop Conditioning and Environment, Ridgetown. Co-author of OMAFRA's biomass factsheet (Using Biomass for Heating Greenhouses in Ontario).

Canadian Propane Association (CPA):

• Shannon Watt — Current President & CEO. On Ontario's 2025 Budget elimination of the Gasoline Tax Act levy on propane (CPA press release, May 16, 2025): "This long-standing recommendation from the CPA marks a critical step toward cleaner, more affordable transportation in Ontario."
• Nathalie St-Pierre — then-President & CEO, 2019. The most-quoted voice from the 2019 CN strike: "agriculture would fall into a lower level tier, unless the propane is needed to heat a barn with livestock in it" (RealAgriculture, November 2019). See op-cpa-emergency-allocation-hierarchy.

Ontario Federation of Agriculture (OFA):

• Keith Currie — then-President, 2019 (now CFA President). 2019 CN strike: "Many of our customers have already been notified by their propane suppliers that they're going to be cut off" (Global News).

Ontario-relevant trade press:

• Greenhouse Canada (monthly).
• The Grower (OFVGA).
• Farmtario (Glacier FarmMedia).
• Better Farming.
• Canadian Florist.
• John Bartok's Greenhouse Management writing (e.g., January 14, 2025 piece on CO2 enrichment is widely cited).

Naming convention reminder. When citing OMAFRA Factsheet 290/27 or Publication 370, the legacy "OMAFRA" name is correct because the publications predate the rebrand. For post-2024 ministry references, use "OMAFA."

Cross-references: reference-omafra-supplemental-co2-greenhouses, reference-omafra-publication-370-greenhouse-floriculture, reference-named-sw-ontario-greenhouse-operators-2026, reference-ontario-grain-industry-voices, op-cpa-emergency-allocation-hierarchy.

Concept: Greenhouse bedding-plant propane load profile (seasonal Feb–early Jun)

Confidence: Estimated.

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 reference-omafra-publication-370-greenhouse-floriculture). Where used, propane CO2 generators target 800–1,000 ppm. See op-greenhouse-propane-co2-enrichment-math.

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 highest-margin growing window.

Cross-references: op-greenhouse-floriculture-ornamental-propane-load-profile (flipped curve), op-greenhouse-seasonal-demand-curve, op-greenhouse-bulk-propane-tank-sizing.

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

Confidence: Verified for setbacks (CSA B149.2-20); Estimated for vaporizer threshold.

Tank sizing for greenhouse installations is driven by burner load and minimum-inventory-floor logic (see op-greenhouse-seasonal-demand-curve 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 op-greenhouse-vegetable-propane-load-profile.

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 reg-csa-b149-2, reg-oreg-211-01-propane):

• 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 reg-tssa-fs-271-24-200-psig-tanks). 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 reg-eccc-e2-plan-propane-threshold.

RSMP threshold. RSMP under O. Reg. 211/01 is generally not triggered for typical own-use greenhouse heating installations under ~19,000 L; see reg-rsmp-greenhouse-private-outlet-threshold 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)

Confidence: Estimated — derived from OMAFRA Supplemental Carbon Dioxide in Greenhouses envelope ratios applied to the Ecostrat vegetable benchmark.

The dominant propane-served greenhouse segment in B&J's SW Ontario service area: 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 op-greenhouse-propane-co2-enrichment-math 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 op-greenhouse-seasonal-demand-curve.

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 op-greenhouse-propane-equipment-types.

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

Confidence: Estimated.

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 reg-eccc-e2-plan-propane-threshold.

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 op-greenhouse-propane-equipment-types.

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: op-greenhouse-floriculture-ornamental-propane-load-profile, op-ontario-greenhouse-industry-snapshot-2024 (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

Confidence: Verified (OMAFRA Supplemental Carbon Dioxide in Greenhouses, Factsheet 290/27, updated July 23, 2025 — see reference-omafra-supplemental-co2-greenhouses).

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 op-hd5-propane-spec-combustion-quality). 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 op-greenhouse-propane-equipment-types.

Cross-references: reference-omafra-supplemental-co2-greenhouses, op-hd5-propane-spec-combustion-quality, op-greenhouse-propane-equipment-types, op-greenhouse-floriculture-ornamental-propane-load-profile.

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)

Confidence: Verified (OMAFRA Publication 370 Guide to Greenhouse Floriculture Production, November 4, 2022 — see reference-omafra-publication-370-greenhouse-floriculture).

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 op-greenhouse-propane-co2-enrichment-math).

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 verify the burner is low-NOx-rated and 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: op-greenhouse-propane-co2-enrichment-math, op-greenhouse-bulk-propane-tank-sizing, reference-omafra-publication-370-greenhouse-floriculture, reference-ieso-greenhouse-energy-profile-study-2019.

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)

Confidence: Verified for NG benchmark; Estimated for propane equivalent.

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 op-ontario-greenhouse-industry-snapshot-2024). 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 op-greenhouse-bulk-propane-tank-sizing.

CO2 enrichment. Vegetable operations typically target 1,000–1,300 ppm CO2 daytime under ideal conditions per OMAFRA Supplemental Carbon Dioxide in Greenhouses (see reference-omafra-supplemental-co2-greenhouses). Propane combustion yields ~1.8 kg CO2/L (see op-greenhouse-propane-co2-enrichment-math). Operators using flue-gas-into-canopy must run low-NOx burners per OMAFRA guidance.

Cross-references: op-greenhouse-floriculture-ornamental-propane-load-profile (much more common on propane in SW Ontario), op-ontario-greenhouse-industry-snapshot-2024, 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).

{
  "faq": [
    {
      "a": "At May 2026 indicative costs, propane at $0.80/L delivers about 13.4 ¢/kWh on an 85%-efficient condensing burner, while industrial natural gas at $0.20/m³ delivers about 7.4 ¢/kWh on the same efficiency. The gap is roughly 1.8× in favour of natural gas. The choice is mostly driven by location: greenhouses outside the Enbridge natural-gas grid (Norfolk, parts of Brant, parts of Oxford) run on propane because no NG service is available.",
      "q": "How does propane compare to natural gas for greenhouse heating in Ontario?"
    },
    {
      "a": "Ecostrat's cap-and-trade compliance modelling used 250,000 m³ of natural gas per acre per year as the Ontario vegetable greenhouse benchmark. On an HHV-equivalent basis (25.3 MJ/L propane vs. 37.5 MJ/m³ NG), that translates to roughly 370,000 L of propane per acre per year for TOV, cucumber, and pepper operations. Floriculture and bedding-plant ranges come in lower; nursery and propagation lower still.",
      "q": "How much propane does an Ontario vegetable greenhouse burn per acre per year?"
    },
    {
      "a": "Risk and Safety Management Plans under O. Reg. 211/01 (Propane Storage and Handling) have been required since 2008 for 'retail outlet, filling plant, cardlock or keylock, private outlet or container refill centre' facilities. Most greenhouses storing propane for their own use do not qualify as private outlets, but the determination is case-by-case by TSSA based on activity, not by storage volume. Practitioner consensus puts the RSMP review threshold near 5,000 USWG (~19,000 L) of on-site storage.",
      "q": "What is the RSMP threshold for greenhouse propane installations?"
    },
    {
      "a": "OMAFRA Factsheet 290/27 (updated July 23, 2025) puts the yield at about 1 L of propane producing 1.55 kg of CO₂. The maximum recommended canopy concentration is 1,000 ppm, with a target band of 800–1,000 ppm for most crops. Flue-gas-into-canopy enrichment requires combustion contamination below 0.04 ppm NOx and 4.5 ppm CO, which is why HD-5 propane and properly serviced burners matter for safe enrichment.",
      "q": "How much CO₂ does propane combustion produce for greenhouse enrichment?"
    }
  ],
  "confidence": "industry-consensus",
  "description": "Ontario greenhouse propane reference: fuel economics vs. natural gas and biomass, CO₂ supplementation math, load profiles, tank sizing, RSMP threshold.",
  "json_ld_type": "Article",
  "wave_1_indexable": true
}