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Unilever and Wonderbag™ for efficient cooking


Enable customers to use less fuel and improve nutrition.


In South Africa, electric cookers and paraffin stoves are most commonly used for cooking and wood is also widely used in poorer households. Emissions from these seriously affect the air quality in homes as well as contributing to climate change through particulates and carbon dioxide emissions. Fuel bills can account for up to a fifth of poor people’s income.


Unilever is supporting the provision of Wonderbags across South Africa – an insulated cooking aid that reduces energy use and helps retain the nutrition of the food being cooked. Wonderbags are poly-cotton filled with expanded polystyrene balls that trap heat. Food just needs to be brought to the boil and then left inside the Wonderbag™ to continue cooking, retaining nutrients and flavour. The bags were developed by South African company Natural Balance.

Unilever partnered with Shoprite stores in KwaZulu-Natal and gave away a Wonderbag™ to every customer buying three 200g packs of their Rajah curry powder.


In the first three weeks of the promotion, Shoprite’s sales of Rajah 200g packs tripled
Improved air quality in homes by reducing smoke
Reduced risk of shack fires caused by paraffin stoves
Households can save around 50% of energy used for cooking. The resultant cost savings empower communities by increasing the cash available for discretionary expenses
Nutritious meals can be prepared ahead of time
Reduced food wastage as food cannot burn or overcook
The manufacturing process creates jobs and develops skills – the 100,000 bags Unilever bought for the trial created 650 jobs. Expanding the initiative to five million bags has led to 8,000 expected jobs.
With regular use, one Wonderbag™ can avoid one tonne of carbon emissions every two years
Reduced total community demand for wood as fuel in rural areas promotes forest regrowth and biodiversity
Polystyrene is re-used instead of being dumped in landfill sites

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