The price of a filter is only one part of a school’s water budget. A meaningful comparison starts with what the school currently spends and the specific service a proposed system would replace.
Separate drinking water from cooking
The World Bank’s ESMAP and World Food Programme report, The State of Cooking Energy Access in Schools, examines institutional cooking and identifies gaps in fuel-use and expenditure information. It is useful context for the difficulty of estimating school energy costs. It is not a measure of the fuel used specifically to boil drinking water. [1]
That distinction matters: a school’s whole firewood bill cannot be counted as potential filtration savings. Fuel for preparing meals remains a separate use.
Compare like with like
Current arrangement
- Water purchases or supply charges
- Fuel specifically used for drinking-water boiling
- Staff time spent preparing and distributing drinking water
- Existing treatment and upkeep costs
Proposed system
- Installation and any tank or plumbing work
- Water and power requirements
- Servicing and replacement filters
- Laboratory testing and provision for repairs
GIZ’s Uganda programme lessons support including maintenance budgets at the planning stage. An apparently inexpensive installation can still need substantial ongoing support. [2]
What this means for Ohm
We intend to build each school proposal around its demand, existing spending and the costs of ongoing care. Where records are incomplete, estimates should be identified as estimates. Any claimed saving must follow the site assessment and a like-for-like comparison; it is not a percentage we can promise in advance.
Explore Ohm’s water approach