Vodafone India launched the cellphone in that country last week, aiming to meet the needs of people in rural areas with an unstable electricity supply.
Vodacom is hoping to unveil the VF 247 phone locally as soon as next month.
"The solar-charging feature is likely to appeal to a whole range of people, but we think it will come in particularly handy in rural areas and townships," said Richard Boorman, executive head of corporate communications at Vodacom.
The phone has integrated solar panels and, depending on the strength of the sunlight and network, Boorman said one hour of charging provided about 10 minutes of talk time.
The phone comes with an FM radio, torch light and speaker.
It charges when exposed to ambient light - even while placed in a room during daylight hours.
The unit went on sale in India at around R440 but local prices are not yet available.
Vodafone is a majority shareholder in Vodacom, and Boorman said the relationship with the international company was beneficial to customers.
"By selling Vodafone's specially developed range of some of the world's lowest-cost mobile phones, we are able to follow through on the promise of expanding access to communications and connecting the unconnected."
But solar power is not the only form of alternative energy being tapped by cellphone companies.
Nokia launched a bicycle charger in June, punted as an "eco-friendly" way to recharge phones and save money. Charging starts at a walking pace of around 6km/h and is as efficient as an electrical charger at a speed of 12km/h.
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