Which Bureau of Energy Efficiency Warangal report pays back fastest for a rice mill that makes its own power from husk: 190, 290 or 1,000 kilowatts?

In three Bureau of Energy Efficiency (BEE) Warangal reports, a rice husk cogeneration set of 190, 290 and 1,000 kilowatts (kW) costs rupees (Rs) 146.88, 180.38 and 314.06 lakh and pays back in 3.72, 3.69 and 3.40 years. The 190 kW report's own table gives a smaller saving than its headline.

The three reports side by side

• 190 kW: cost Rs 146.88 lakh, 1,596 megawatt hours (MWh) of power a year, benefit Rs 39.42 lakh, payback 3.72 years, internal rate of return 13.77 percent, printed carbon dioxide (CO2) cut 822.83 tonnes. Husk burnt rises from 10,220 to 11,352 tonnes a year.
• 290 kW: Rs 180.38 lakh, 2,436 MWh, Rs 48.87 lakh, 3.69 years, 12.77 percent. The text gives a CO2 cut of 955 tonnes, but the summary table has no CO2 line. Husk 12,776 to 15,135 tonnes.
• 1,000 kW: Rs 314.06 lakh, 8,400 MWh, Rs 92.40 lakh, 3.40 years, 15 percent, CO2 1,676.55 tonnes. Husk 14,142 to 26,570 tonnes.
• All three assume 350 days of 24 hours, husk at Rs 1.8 a kilogram and grid power at Rs 3.75 a kilowatt hour (kWh). The reports print the power as megawatts (MW) a year; 190 kW x 8,400 hours is 1,596,000 kWh, so we read it as MWh.

How the saving is built

Each report prices the extra husk for power against the grid. The extra fuel is 193, 281 and 1,473 kilograms an hour. Per kWh that is 1.02, 0.97 and 1.47 kilograms of husk, our arithmetic, so the 1,000 kW set burns about 45 percent more husk for each unit than the 190 kW set.

Generation cost a unit is Rs 2.05 for the 190 kW set (which includes Rs 1,000 a day of operating cost), Rs 1.74 for the 290 kW set and Rs 2.65 for the 1,000 kW set. Against Rs 3.75 that leaves Rs 1.70, Rs 2.01 and Rs 1.10 a unit. The big set wins on scale, not on margin: more units, thinner margin.

Where the reports do not add up

• 190 kW: Annexure 3 gives a saving of Rs 1.70 a unit, which on 1,596,000 kWh is Rs 27.13 lakh. The headline Rs 39.42 lakh is Rs 2.47 a unit; that figure appears only in the text and in Annexure 4, and Annexure 3 does not produce it. At Rs 27.13 lakh the payback is 146.88 / 27.13 = 5.4 years, not 3.72. The text also gives net present value as Rs 15.34 lakh against Rs 16.60 lakh in the summary.
• 290 kW: the annexure labels Rs 1.74 as the cost of grid power and Rs 3.75 as the cost of generation. The arithmetic only works the other way round: 12,139 rupees a day of extra husk over 6,960 kWh is Rs 1.74 to generate, and Rs 3.75 is the grid price.
• 1,000 kW: the cost table in the body totals Rs 299.79 lakh; the summary and payback use Rs 314.06 lakh, which is Rs 299.10 lakh plus Rs 14.96 lakh listed as engineering, procurement and construction cost.

The carbon figures

The printed CO2 cuts come to 0.52 tonnes a MWh in the 190 kW report, 0.39 in the 290 kW text and 0.20 in the 1,000 kW report, our arithmetic. The three reports share one grid price and one state, so one factor would be expected. The reports show no factor, and the husk they burn is a renewable fuel. Take the CO2 lines as unchecked, and use the current grid factor for your own estimate.

The 290 kW report, rebuilt

• Fuel with cogeneration 1,801.83 minus 1,520.83 now = 281 kilograms an hour more. 281 x 24 x Rs 1.8 = Rs 12,139 a day
• Power: 290 x 24 = 6,960 kWh a day, so Rs 12,139 / 6,960 = Rs 1.744 a kWh to generate
• Grid Rs 3.75 minus Rs 1.744 = Rs 2.006 a kWh. Over 2,436,000 kWh: Rs 48.87 lakh
• Payback: 180.38 / 48.87 = 3.69 years

All figures are the report's own. Rs 12,139 a day and the unit cost use the report's husk price and ignore operating and maintenance cost, as the 290 kW and 1,000 kW annexures do.

What Senseible does here

Senseible reads fuel invoices and electricity bills into monthly records, so the electricity bills and fuel invoices you upload give a year of use before a change to compare against. The kWh from your own turbine come from its meter, which you add.

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Sources: BEE, Detailed project report: rice husk cogeneration 190 kW, Warangal rice milling cluster (SAMEEEKSHA), BEE, Detailed project report: rice husk cogeneration 290 kW, Warangal rice milling cluster (SAMEEEKSHA), BEE, Detailed project report: rice husk cogeneration 1,000 kW, Warangal rice milling cluster (SAMEEEKSHA)

Last reviewed 2026-11-05. Report figures are from BEE's Small and Medium Enterprises (SME) programme project reports, at the report year's prices. Check today's husk price, your grid tariff and a current quote before you rely on the payback.