Why does the Bureau of Energy Efficiency (BEE) Solapur report for 8 rapier looms print a power saving of 4,680 kilowatt hours when the 4 loom report prints 18,720?

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BEE's Solapur reports price 4 rapier looms at rupees (Rs) 27.68 lakh and 8 at Rs 49.81 lakh, with yearly benefits of Rs 12.83 and 25.66 lakh. The 8 loom summary prints 4,680 kilowatt hours (kWh) saved; that is one loom's figure, and eight save 37,440. Both use the same per loom case: four old shuttle looms drawing 8.4 kWh a day each, 33.6 in all, make 48 kilograms of cloth with 4 weavers. One rapier loom draws 18 kWh a day, makes 50 kilograms with 1 weaver. Saving 15.6 kWh a day x 300 days = 4,680 kWh a loom a year. The benefit per rapier loom is Rs 3,20,700 in both reports: Rs 11,700 from power at Rs 2.50 a kWh, Rs 1,56,000 from labour, Rs 1,35,000 from better cloth and Rs 18,000 from maintenance. Four looms: Rs 12,82,800. Eight: Rs 25,65,600. Cost, 4 looms: Rs 26.00 lakh equipment, 1.00 civil work, 0.68 interest, Rs 27.68 lakh. 8 looms: Rs 47.06 lakh, 1.50, 1.21, Rs 49.81 lakh. Per loom that is Rs 6.92 lakh and Rs 6.23 lakh, so eight cost 10% less each. Printed indicators, 4 against 8 looms: payback 2.15 and 1.94 years (27.68 / 12.83 is 2.16; 49.81 / 25.66 is 1.94), internal rate of return (IRR) 25.25% and 30.56%, net present value (NPV) Rs 12.04 and 29.73 lakh, 10 days of downtime each. The 8 loom summary table says electricity saving 4,680 kWh a year. Its own Table 3.1 and its carbon line say otherwise: 15.6 x 300 x 8 = 37,440 kWh, and the 32 tonnes of carbon dioxide (CO2) it prints is exactly twice the 4 loom report's 16. The 4,680 is one loom's saving. The 4 loom report prints the right total, 18,720. The 8 loom equipment cost is Rs 47.06 lakh in the cost table and Rs 47.09 lakh in the text. The total of Rs 49.81 lakh fits neither exactly: 47.06 + 1.50 + 1.21 = 49.77 and 47.09 + 1.50 + 1.21 = 49.80. Table 3.1 in both labels Rs 11,700 as "Rs in lakh" and 33.6 as "kWh/annum"; they are rupees and kWh a day. The labour saving rests on one weaver at Rs 7,000 a month replacing four at Rs 5,000 each (Rs 20,000), a cut of Rs 13,000 a month, Rs 1,56,000 a year a loom. That is 49% of the benefit. Check what your own weavers are paid before you count it. The reports print 16 and 32 tonnes, 0.855 tonne of CO2 for each megawatt hour. At the Central Electricity Authority (CEA) grid factor for financial year (FY) 2025-26, 0.675 kilograms a kWh, 18,720 kWh is 12.6 tonnes and 37,440 kWh is 25.3. Power is a small part of the benefit: Rs 11,700 of the Rs 3,20,700 a loom, 3.6%. Judge the loom on output, labour and cloth quality; power alone would take decades to pay back. Measure your own shuttle looms: kWh a day and kilograms a day, for a month. Keep meter readings and kilograms woven before and after. A buyer asking for kWh and CO2 per kilogram will want that pair.

Why does the Bureau of Energy Efficiency (BEE) Solapur report for 8 rapier looms print a power saving of 4,680 kilowatt hours when the 4 loom report prints 18,720?

The two reports side by side

The 4,680 kWh in the 8 loom summary

Other printed figures that do not tie

What the power saving is worth in carbon

Before you buy

Eight looms, rebuilt

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