Does your café have to close during every power outage?
Till, lighting, refrigeration or coffee machine: choose which equipment needs backup and plan suitable runtime for your shop in Tunisia.
A café can maintain some services during an outage if the necessary equipment has suitable backup power. The first decision is what needs to keep running: payments, lighting, refrigeration, drink preparation or full customer comfort. These goals require different power levels and energy reserves.
If your premises experience outages, start with your own records: duration, timing, equipment affected and consequences. These observations are more useful for the assessment than assuming the same outage frequency everywhere in Tunisia.
Three key points: size a battery for specific equipment; its kWh rating alone cannot confirm power capacity; keeping the electricity on does not, by itself, guarantee every business service.
1. Define the service you want to maintain
Start with a short list. A till, a few lights and essential refrigeration can form an initial scope. The coffee machine, heating appliances and several air conditioners may require much higher power.
| Priority to assess | Possible equipment | What to check |
|---|---|---|
| Payments | Till, payment terminal, local network | Tolerance to interruption and connection availability. |
| Essential operations | Essential lighting, controls | Circuits actually needed and target duration. |
| Food storage | Refrigerators, display fridges | Compressor startup and temperature monitoring. |
| Preparation | Coffee machine, water heater, cooking appliances | Simultaneous power demand and actual operating cycles. |
| Comfort | Air conditioning, ventilation | Power demand and priority during the outage. |
An adapted service can be organised around these priorities. Continued operation also depends on safety, hygiene and the equipment actually available. A powered till cannot replace a machine essential for preparing orders.
2. A simple example: three hours of essential service
Consider a fictional example, to be replaced with measurements from your premises:
| Selected load | Assumed average power |
|---|---|
| Till and local network | 60 W |
| Selected lighting | 120 W |
| Essential refrigeration, including operating cycles | 250 W |
| Average total | 430 W, or 0,43 kW |
Over three hours, energy demand is 0,43 × 3 = 1,29 kWh. If the scenario assumes 80 % of nominal capacity is usable and overall conversion efficiency is 90 %, the calculated energy minimum is 1,29 ÷ (0,80 × 0,90) ≈ 1,79 kWh of nominal capacity.
This result does not select a battery. Peaks, reserves, temperature, ageing, inverter power and recharging between outages still need checking. The 250 W refrigeration load is a hypothetical average, not the power required at startup.
Specify “café / tea room continuity”, your priority equipment and desired backup duration. With your name, phone number and email, the team can prepare a free, no-obligation assessment tailored to your business.
3. The coffee machine can change the entire system sizing
In the same example, adding a heating appliance assumed to draw 2 kW continuously raises the total to 2,43 kW. Three-hour energy demand becomes 7,29 kWh, or about 10,13 kWh of nominal capacity under the same availability and conversion assumptions.
This comparison illustrates why scope matters. It does not describe how every coffee machine works: thermostats and usage change consumption. Nameplates, manuals and measurements provide the basis for recalculating accurately.
4. Check power capacity and transfer to backup
Motors and compressors may need more power at startup than during steady operation. Victron’s technical guide distinguishes continuous power, surge power and appliances used simultaneously. Source: choosing an inverter/charger, Victron Energy.
The till may also restart if the transfer is not fast enough for it. A small uninterruptible power supply, or UPS/ASI, can be considered for sensitive equipment alongside the main storage system. Its specifications must suit the equipment concerned. Source: UPS functions, Eaton.
Keeping the router powered does not guarantee that the operator’s network will remain available. Planning backup payments and connectivity is therefore also part of organising your business.
5. Assess the complete installation and Tunisian requirements
For a solution connected to solar PV or the grid, compatibility between the battery, inverter, protection devices and backup architecture must be checked. STEG’s July 2026 technical reference covers storage and standalone operation among other topics. Source: STEG technical reference.
STEG’s announcement on home batteries explicitly concerns residential customers. It is not enough to establish the conditions applicable to a café: your business application and selected equipment must be assessed.
6. Prepare an assessment that fits your business
Gather your bills, equipment list and model details, operating hours and observed outages. Also specify what can be temporarily switched off. The assessment then compares backup duration, continuity, recharging, maintenance and budget. The business solar PV solution can complement this review for daytime consumption.
Explore further: calculate the cost of an outage, prioritise refrigerators and compare batteries, generators and UPS. The cash/credit example separately explains a solar project’s financial flows.
— Start with your equipment and desired backup duration. Also browse all our guides and examples.