With the rapid increase in the price of electricity and water over the past few years, the question is: what does a shower or bath cost in South Africa in 2017?
Most South Africans are aware of the rapidly rising price of electricity (a 300% increase in the period 2007-2015 alone), but the price of water has also been increasing rapidly over the past few years.
For example, here are the water & sanitation tariff increases effective July 2017 for the four major metropolitan areas:
- Ethekwini 17%
- City of Johannesburg 12.2%
- City of Tshwane 10.2%
- City of Cape Town:
- 13.2% for 6 – 10.5 kl (kilolitres)
- 29.7% for 10.5 – 20 kl
- 27.2% for 20 – 35 kl
- 128.8% for 35 – 50 kl
These increases are all much higher than inflation. All these municipalities have also done away with the free water allocation of 6 000 litres (6 kilolitres), except for people registered as indigent.
Of course, there is a serious drought in Cape Town, and so the increases seen there might be more justifiable.
South Africans tend not to think twice about the cost of a shower or bath, since both electricity and water used to be very inexpensive.
Is this still true in 2017? We did some calculations and the result is an eye-opener.
For an average middle-class household in South Africa (LSM7-10), a 10-min shower costs almost R13 if you have a ‘standard’ 15 litre/min showerhead! This is about R1.30/min. By changing to a low-flow showerhead and reducing shower time to 6 minutes, you can dramatically reduce this to just over R4 per shower (or 70c/min).
In either case, it appears that the days of ‘cheap’ showers are numbered, and we can all do with being more aware of just how much water & electricity we use in the shower or bath.
Conventional wisdom has it that showering uses less water than running a bath. However, a typical bath uses 90 litres of water, so if you shower for longer than 6 minutes with a ‘standard’ showerhead, you will actually use more water than if you had a bath… With an average shower time internationally of 8 minutes, a shallow bath might actually be better for your pocket and the environment!
Of course, even better than a shallow bath is to switch to a low flow showerhead and have shorter showers… City of Cape Town recommends showering for less than 2 minutes, and switching to low-flow showerheads (less than 10 litres/min) is compulsory according to City of Cape Town bylaws.
The graphs below show more detailed information on water & energy use and cost per shower for normal & low-flow showerheads, and compared to a ‘standard’ 90 litre bath.
References, methodology & assumptions for calculations
- Shower & bath temperature of 40°C. See e.g. Lawrence JC & Bull JP. 1976. Thermal conditions which cause skin burns. Engineering in Medicine 5(3):61-63.
- Average residential water consumption data was obtained from: Viljoen N. 2016. Presentation: City of Cape Town Residential Water Consumption Trend Analysis 2014/15. Last accessed: 21/08/2017.
- Average residential electricity consumption data was obtained from: Goliger, A. and Cassim, A. (14 and 15 July 2017). Tipping Points: The Impacts of Rising Electricity Tariffs on Households and Household Electricity Demand. 3rd Annual Competition and Economic Regulation (ACER) 2017 Conference, Dar es Salaam, Tanzania. Last accessed: 21/08/2017.
- Average bath uses about 90 litres of water. Waterwise. Last accessed: 12/09/2017.
- “Normal” or standard showerheads use 15 litres of water per minute or more, and low flow showerheads use about 8 litres water per minute. Eskom fact sheet on showerheads. Last accessed: 12/09/2017.
- Average effective residential water & electricity tariffs were calculated from the published 2017/18 tariffs of the following four metropolitan municipalities: City of Johannesburg, City of Tshwane, City of Cape Town and Ethekwini, using the average residential water and electricity consumption values for LSM7-10 obtained from the above references.
- For ‘lower income’ households, the average water & electricity tariffs are somewhat lower across the four municipalities (due to lower average consumption), at R1.65/kWh for electricity and R23.47/kilolitre for water & sanitation. This yields a cost per bath of R6.42, a cost per 10-minute ‘normal showerhead’ shower of R10.70/shower, and a cost per 6-minute low-flow showerhead shower of R3.40/shower.
- Energy cost of hot water based on heating water from 15 to 60°C, which requires approximately 5.22 kWh per 100 litre.
- A study by the Alliance for Water Efficiency also found a shallow bath to be better than a long shower with a high flow showerhead.
- Average shower time: a recent study at a South African university found an average shower time of over 9 minutes.