# What does a 3 kW solar plus aero-generator hybrid give a Jorhat tea factory?

Canonical: https://senseible.earth/answers/tea-factory-solar-aero-generator-hybrid-3kw-co2

The BEE and SAMEEEKSHA report for the Jorhat tea cluster puts a 3 kW solar plus aero-generator hybrid at 18.9 MWh a year, using waste air from the withering trough, shown as 19.47 tonnes CO2. It uses a factor of 1.03 kg per kWh.

## How it works

Withering fans push air through the leaf. The air leaving an enclosed trough moves at an average 10.68 metres a second. A small wind turbine takes power from it for the 10 hours a day the fans run, and solar panels charge a battery bank that gives back-up for the other 14 hours.

## Where 18.9 MWh comes from

- 250 days with waste air and sun: 72 kWh a day, 18,000 kWh.
- 30 days with waste air only: 30 kWh a day, 900 kWh.
- Total: 18,900 kWh a year.

## How big is that

A typical factory in the cluster uses about 498,000 kWh a year, so this covers about 3.8%. The report lists three withering fans feeding one turbine, and about 45 days for installation and commissioning.

## Which factor to use

The report converts 18.9 MWh to 19.47 t with 1.03 kg per kWh. For a buyer or loan file use the CEA grid factor for your bill's year, which is lower.

## Worked CO2 at two factors

- Generation: 18,900 kWh a year.
- The report's 1.03 kg per kWh: 18,900 x 1.03 = 19,467 kg, or 19.47 t.
- CEA grid factor, FY 2025-26, 0.675 kg per kWh: 18,900 x 0.675 = 12,757 kg, or 12.8 t.

The report dates from 2010 and is for one installation.

## What Senseible does here

Senseible reads grid and diesel bills for tea factories into kWh and CO2 per month, so the effect of a solar or turbine addition is measured on the bills.

- [Rooftop solar carbon payback](https://senseible.earth/answers/carbon-payback-of-rooftop-solar-panels)
- [Which CEA grid factor version](https://senseible.earth/answers/which-cea-grid-factor-version-for-which-year)
- [Carbon calculators](https://senseible.earth/calculators)

Sources: [SAMEEEKSHA and BEE, DPR: solar and aero generator hybrid power system, Jorhat tea cluster](https://sameeeksha.org/pdf/dpr/Jorhat_tea_cluster/12_Solar_aero_generator_hybrid_power_system_Jorhat.pdf)

Last reviewed 2026-11-03.