grabowski
9640a4f075
PEA tariff schedule (May 2023 onward, still current) filed under docs/finance/pea/; Ft 0.1623 THB/kWh for Sep-Dec 2026 from the PEA Ft page. The plant falls under Schedule 3.2.2 (Medium General Service, TOU, 22 kV). New section in sustainability.md: blended ~3.81 THB/kWh for two-shift production plus 132.93 THB/kW demand charge; electric steam ~4.7M-5.5M THB/yr at maturity against ~0.35M-0.8M of biomass fuel; self-consumed PV worth ~3.7 THB/kWh (~4.5-7 yr payback); solar thermal not recommended; the battery earns little from TOU arbitrage or peak shaving. biomass.md, scale.md, the utilities CSV note and the README follow.
4.6 KiB
Biomass Fuel Strategy
If the steam boiler goes the biomass route (see the options in sustainability and the Getabec candidate in the utilities CSV), the fuel comes from two sources: the team's own 60 rai of currently unused land, and northern Thailand's agricultural waste market. Figures below are planning estimates, plus or minus a wide margin, to be refined against the actual boiler choice and duty cycle.
Demand: what the boiler would burn
The 400 kg/h boiler is roughly 300 kW thermal at full fire. With the heat recovery architecture trimming the load and realistic duty cycles:
- Mature plant (semi-auto plus automated lines, two shifts, ~300 days/yr): roughly 350 to 400 tonnes of air-dry wood per year (at ~80% boiler efficiency and ~4 kWh/kg air-dry wood)
- Early operations (one press line, single shift): roughly a quarter of that, ~90 to 100 t/yr
The 60 rai: own-grown fuelwood
60 rai is 9.6 hectares. Managed as short-rotation coppice (planted once, harvested on a 2 to 4 year cycle, regrowing from the stump), fast species proven in Thailand (eucalyptus, acacia, leucaena, bamboo) yield roughly 8 to 14 air-dry tonnes per hectare per year. So the land can sustainably supply about 80 to 135 t/yr:
- Enough to cover most or all of early operations
- About a quarter to a third of mature two-shift demand
That makes the land a meaningful supplement and a strong brand story ("records pressed with steam from our own trees"), not a complete fuel supply.
The classification check comes first
The land is currently classified as forestry, and in Thailand that carries legal weight. Before a single tree enters the fuel plan:
- Verify the parcel's actual status: clean Chanote title vs Sor Por Kor vs National Forest Reserve. Planting, harvesting, and transporting trees, even self-planted ones, can be restricted depending on classification, and some species are restricted regardless.
- If eligible, register the plantation under the forest plantation framework, which legalizes grow-and-harvest cycles and the transport paperwork.
- If the parcel carries actual standing forest, it should not be harvested for fuel: that would undercut the sustainability commitments the plant is built on. Coppice belongs on the degraded or empty portions.
Filling the gap: the northern biomass market
The region fills the remainder easily and cheaply:
- Longan orchard prunings: Lamphun is Thailand's longan heartland and prunings are an established traded fuel
- Sawmill and wood-processing residues
- Corn cobs and rice husk: abundant regional crop wastes; a Getabec-class solid-fuel boiler is designed for exactly this fuel mix
- Buying from local farmers also strengthens the local-sourcing story that already runs through packaging and PVC
Logistics on site
To reflect in the facility planning: a fuel storage shed (biomass must be kept dry; monsoon-season storage sizing matters more than dry season), chipping for coppice wood, ash handling, and the emissions stack that comes with solid fuel. These are the capex/opex adders that the biomass premium in the utilities CSV (roughly 4M to 7M THB for the boiler package vs 2.5M to 4M electric/gas) partially reflects; fuel handling and storage are additional.
Decision framing
- Biomass makes the steam genuinely renewable and pairs with cheap northern fuel, at the cost of higher capex, fuel logistics, ash, and an emissions point
- The 60 rai tilts the economics and the story further toward biomass, but only after the land-title check clears
- The electric boiler remains the alternative: cleanest permitting, no fuel logistics, but effectively grid-powered steam at a ~300 kW draw. On PEA's time-of-use tariff that costs ~4.7M to 5.5M THB a year at mature load against ~0.35M to 0.8M of fuel for biomass, and ~1.4M to 1.7M against ~0.1M to 0.2M at early load, because the demand charge follows the boiler's full-power draw (estimates; see the grid tariff). The electric boiler is the more efficient machine; biomass is the far cheaper heat
- A staged path is possible: start electric (fast, clean permitting), plant the coppice now (first harvest in 2 to 4 years), and add the biomass boiler at the automated-line expansion when demand and the fuel supply have both matured. At the tariff above that is a permitting and logistics choice, not a cost one: every year on electric steam costs roughly 1.2M to 5M THB more than biomass, so the switch should come as soon as the permit and a fuel contract are in place