Compost unit · formula, drawing and price in one placeMake your own compost.
Control your crop.
Two aerated bunkers and a sealed tunnel turn straw and manure into a batch of spawn-ready compost every 15 days. Choose the unit and the rooms it feeds; the formula, the drawing, the price and the saving below all follow.
Your compost unit
Every figure on this page updates as you change these.
It all starts with wheat straw
The formula, by weight
MushroomWale’s working formula: the wheat straw commercial formula for one batch of the 20 T unit, worked out by our compost calculator: 2.5 t of compost from each tonne of straw, with a 5% handling margin. For reference, the compost SOP also quotes a widely used Indian formula per tonne of straw: 400–500 kg poultry manure, 30 kg urea, 25 kg gypsum and 30 kg wheat bran.
Mixed with manure, bran, urea and gypsum on the wetting slab, then moved to the bunkers.
The base substrate and carbon source.
baseThe main nitrogen source.
500 kg / t strawA supplement mixed in with the manure.
75 kg / t strawAdditional nitrogen, dosed with care.
15 kg / t strawBuffers pH and keeps the structure open.
30 kg / t strawThe unit, drawn to scale
What you are paying for, seen from above and from the side: a spigot floor and air main in each bunker, a sealed tunnel with a plenum floor, recirculation blower and probes.
| Batch | 20 t · 2,000 bags |
| Cycle | 15 days |
| Bunker blowers | 2 × 3.5 HP |
| Tunnel blower | 1 × 7.5 HP |
| Flex air pipe | 600 ft |
| Build time | 45–60 days |
- All dimensions in feet and inches; read, do not scale.
- Walls, slab, drains and roof are civil work by the client, built to our drawing.
- Wall and tunnel heights are set on the construction drawing for your site.
Swipe the drawing sideways to see all of it.
Air and aeration
- Main manifold: 8 inch HDPE polymer pipe
- Under-floor distribution: 4 inch PVC pipes embedded in RCC
- Reducers: 8 inch → 4 inch
- Spigot piping: PVC perforated pipes inside bunkers
- Holes drilled AFTER RCC construction only
Controls and sensors
- IoT controller with Phase-I + Phase-II programs
- Temperature sensors: 5–7
- Ammonia logic & runtime logging
- Remote monitoring with alerts
Civil requirements
- RCC floor 6–8 inches
- Drain trench 8–12 inch
- Wetting slab sloped 2 in (20 T) / 4 in (30 T) along its length
- Loader-friendly flooring
- Anti-skid broom finish
One batch, by temperature
The number that matters in compost is the core temperature. Each stage of the Phase-I + Phase-II cycle holds the set-point band our controller runs; the same cycle serves both units.
Pre-wetting
Initial moisture treatment
Phase I (Bunkers)
Turning Day 3, 5, 7 | Core: 70–78°C | Moisture: 68–72%
Phase II (Tunnel)
Pasteurize: 58–60°C | Condition: 45–50°C | Exit ammonia: under 10 ppm
Cool-down & Bagging
Spawning start | Movement to grow rooms
The price, line by line
The same lines and rates as your compost quotation. Civil work, raw material and water are yours; GST at 18% is added on the quotation.
| Item | Qty | Rate | Amount (₹) |
|---|---|---|---|
| Piping & fittings₹2,25,780 | |||
| 8″ HDPE pipes | Lot | 40,230 | |
| 8″ fittings | Lot | 33,300 | |
| 4″ fittings | Lot | 36,900 | |
| Flex pipe | 600 ft | ₹192.25 / ft | 1,15,350 |
| Blowers₹1,60,570 | |||
| Bunker blowers · 3.5 HP | 2 nos | ₹46,940 / no | 93,880 |
| Tunnel blower · 7.5 HP | 1 no | ₹66,690 / no | 66,690 |
| Control panels₹62,550 | |||
| Control panel · tunnel | 1 no | 33,210 | |
| Control panel · bunkers | 1 no | 29,340 | |
| Infrastructure₹1,97,100 | |||
| Solvent | Lot | 13,500 | |
| Installation | Lot | 49,500 | |
| Electrical | Lot | 44,100 | |
| MS gate | 1 no | 90,000 | |
| Unit total · ex-GST | ₹6,46,000 | ||
Civil work for the bunkers, tunnel and slab (client scope) is ₹8–10 lakh a unit. Build time 45–60 days. Yard machinery for 212 kg a day of mushrooms (4 × 18×40 rooms), also client scope: tractor trolley with loader, ₹15,00,000.
Own compost saves ₹20.8 a kilo
Compost cost per kilo of mushroom grown
saved a year on 76,800 kg from 4 × 18×40 rooms
₹6.5 lakh equipment + GST + ₹8–10 lakh civil
1 × 20 T, ex-GST
The compost yard, laid out
Straw comes in at the store, is wetted and mixed on the slab, goes through the bunkers and tunnel, and leaves as compost for the rooms. One direction, no cross-over.
Sizes and land are the ones our Design my project tool uses. The slab, store and yard are civil work by you, built to our drawing.
Two units, one standard
All MushroomWale compost units follow the same engineering, airflow, RCC floor design, mixing-yard requirements and Phase-I + Phase-II cycle, suited to Indian conditions up to 50 °C.
2000-Bag Compost Unit14×30 System | RECOMMENDED3000-Bag Compost Unit14×40 System | |
|---|---|---|
| Core chambers | ||
| Bunker 1 | 14 ft × 30 ft | 14 ft × 40 ft |
| Bunker 2 | 14 ft × 30 ft | 14 ft × 40 ft |
| Closed tunnel | 14 ft × 30 ft | 14 ft × 40 ft |
| Supporting areas | ||
| Wetting & mixing slab | 45 ft × 50 ft | 45 ft × 70 ft |
| Slope | 2 in over the 50 ft slab | 4 in over the 70 ft slab |
| Capacity | ||
| Bags per cycle | 2,000 | 3,000 |
| Bag weight | 10 kg | 10 kg |
| Cycle duration | 15 days | 15 days |
| Tons per cycle | 20 ton | 30 ton |
| Cycles per month | 2 | 2 |
| Monthly output | 40 ton | 60 ton |
| Daily equivalent | 1.33 ton/day | 2 ton/day |
| Blowers and sensors | ||
| Bunker blower 1 | 3.5 HP | 5 HP |
| Bunker blower 2 | 3.5 HP | 5 HP |
| Tunnel blower | 7.5 HP | 10 HP |
| Temperature sensors | 5–7 | 7 |
| Price | ||
| Equipment, ex-GST | ₹6,46,000 | ₹7,08,000 |
| Civil work (client scope) | ₹8–10 lakh | ₹12–14 lakh |
| Build time | 45–60 days | 60–90 days |
Get the compost quotation
Ask us for an estimate, or build the itemised quotation yourself: choose the unit, add your details and download the PDF or send it on WhatsApp.
