Single-storey retail premises
Retail Business, Nairobi
Grid-tied rooftop solar · illustrative
A rooftop solar design for a retail business with refrigeration and lighting loads that closely follow daylight trading hours.
Commercial
Guest House, Naivasha
A solar water heating design for a guest house where electric geysers make up a large share of the monthly electricity bill.
- Property type · illustrative
- Eight-room guest house
- Location · illustrative
- Naivasha
- System type · illustrative
- Solar water heating
- Category
- Commercial
Stock photography used for illustration. Not images of this scenario.
Project overview
This project looks at replacing most of the electric water heating in an eight-room guest house with roof-mounted solar water heaters. Hot water demand is high and predictable, peaking in the early morning and evening when guests shower.
The challenge
A fictional scenario
In this fictional scenario, each room has its own electric geyser, and water heating is the single largest item on the electricity bill. The owner wants to cut that cost without guests noticing any change in hot water availability, including after cloudy days.
Proposed system configuration
Evacuated-tube solar water heaters on the roof feed insulated storage tanks serving groups of rooms. The existing geyser elements are retained as backup on timers, so they only top up the water when solar input has not been enough.
Installation considerations
- Roof structure checked for the weight of full tanks before positions are finalised.
- Collectors oriented for the best sun exposure, clear of shading from the mature trees on the plot.
- Water quality tested, as hard water around the lake affects scaling and maintenance intervals.
- Work phased room by room so the guest house stays open during installation.
Illustrative outcome
What the design aims to achieve
- 01
Most daily hot water demand is designed to be met by solar, with electric elements topping up only when needed.
- 02
Timers prevent backup elements from heating water that the sun would have heated later in the day.
- 03
Staff have a simple maintenance routine covering valves, anodes and collector cleaning.
Outcomes describe design intent for a fictional scenario. They are not measured results or a guarantee of performance. Real-world results depend on actual consumption, weather, equipment and site conditions.
More projects
Related projects
Professional services office
Small Office, Nakuru
Hybrid essential-load backup · illustrative
A hybrid backup design for a small office that needs computers, connectivity and lighting to stay available during outages.
Primary day school
Day School, Machakos
Hybrid solar + battery · illustrative
A hybrid design for a day school whose energy use falls almost entirely within daylight hours, with backup for the computer lab and office.
Have a similar property or energy challenge?
Tell us how you use power, what matters most to you and what you’d like solar to do. We’ll talk you through the options in plain language. No technical knowledge needed.