How to Spread Your Load

Here's the most important thing to understand about living with solar: when you use electricity matters just as much as how much you use. Your panels produce power in a curve that peaks around midday and drops to zero at sunset. If you run all your heavy appliances in the evening, you're draining your battery instead of using free solar power.

Spreading your load means distributing your electricity usage across the day so the heaviest consumption lines up with peak solar production. It sounds simple, but it's the single most impactful behaviour change you can make after going solar.

The Solar Production Curve

On a typical clear day in Zimbabwe, your panels follow a predictable pattern:

The peak window from 10 AM to 2 PM is your golden opportunity. During those four hours, your panels are producing at or near their maximum. Any appliance running during that window is essentially running on free electricity.

The Morning Routine

Most households make the same mistake every morning: the geyser kicks in at 5 AM, someone irons school uniforms at 6 AM, and the washing machine starts at 7 AM. By the time the sun is strong enough to help, you've already drained your battery or pulled heavily from the grid.

A better approach:

1. 6:00 – 7:00 AM: Lights, kettle, phone chargers. These are small loads your battery handles easily.
2. 7:30 – 8:30 AM: Start the geyser. Panels are producing enough to contribute, and the geyser has time to heat fully before midday.
3. 9:00 AM onwards: Ironing, if you need to. By 9 AM, panels are producing 40-60% and rising.

The key principle is staggering. Don't run the geyser, iron, and washing machine at the same time. Each one draws 1.5-2.5 kW. Running all three simultaneously means a 6+ kW demand that exceeds most residential inverters. Instead, run them one after another, starting with the geyser since it takes longest.

The Midday Window

Between 10 AM and 2 PM, your panels are working at full capacity. This is the time to run power-hungry appliances that you might otherwise avoid:

• Washing machine — a full cycle takes 1-2 hours, fits perfectly in the midday window
• Pool pump — set the timer for 10 AM to 2 PM instead of overnight
• Borehole pump — fill your tanks during peak sun (more on this in our borehole guide)
• Dishwasher — run it after lunch instead of after dinner
• Vacuum cleaner — midday cleaning uses free power
• Charge devices — laptops, tablets, power banks, rechargeable torches

This is also the best time to pre-cool your fridge and freezer. Turn the thermostat down slightly at 10 AM. The fridge builds up a reserve of cold that carries it through the evening without working as hard. Turn the thermostat back to normal at 3 PM.

The Afternoon Shift

From about 2 PM, solar production starts declining. By 4 PM, it's dropped significantly. This is the time to transition to essential loads only:

• Finish any laundry or dishwasher cycles that are still running
• Switch off the pool pump
• Stop charging devices that are already topped up
• Keep lights off — there's still natural daylight

The afternoon is a good time for tasks that don't use much electricity: homework, cooking on gas, reading. Save your battery capacity for the evening.

Evening Strategy

After sunset, your house runs entirely on battery power (or grid, if it's available). Every watt you use now is a watt that won't be there at 3 AM.

Keep evening usage minimal:

• LED lighting only. A single LED bulb uses 7-10W compared to 60-100W for an incandescent. Switching to LEDs across your house can cut your lighting load by 80%.
• Television and Wi-Fi router are fine — they draw relatively little power (80-150W combined).
• No ironing, washing machine, or dishwasher after sunset.
• No electric cooking if avoidable — use gas or plan meals that don't need the oven.
• Set the geyser timer to off. There's no reason to heat water at night.

The Load-Shedding Factor

Here's a silver lining that surprises many people: load shedding during peak solar hours can actually work in your favour.

When the grid is off during the day, your solar system handles everything. You're running on your own power, paying nothing, and not drawing from the grid at all. If the grid comes back at 6 PM, your battery is fuller than it would be if the grid had been available all day (because the inverter was sending surplus solar to the battery instead of back-feeding the grid).

The worst load-shedding schedule for solar users is grid off from 6 PM to midnight. That's when you need your battery most, and if the grid was on all day, you might not have charged the battery as aggressively.

Plan for the worst schedule:

• Check if your inverter's charge settings prioritise battery charging during solar hours
• Set a minimum battery reserve (usually 20-30%) so the inverter starts grid-charging in the afternoon if solar wasn't enough
• On days when you know load shedding is coming in the evening, be extra conservative with afternoon loads

Practical Tips That Make a Real Difference

Timer Switches

Invest in plug-in or hardwired timer switches for:

• Geyser: 8 AM – 2 PM only. This is the single biggest load in most homes.
• Pool pump: 10 AM – 2 PM. A 750W pump running for 4 hours in peak solar costs you nothing.
• Towel rails and underfloor heating: Off unless it's peak solar hours.

Pre-cooling and Pre-heating

Your fridge, freezer, and house itself act as thermal batteries:

• Fridge/freezer: Turn the thermostat colder at 10 AM, back to normal at 3 PM. The built-up cold carries through the night.
• Geyser: Heated to maximum by 2 PM, the insulated tank holds temperature for 6-8 hours. You'll still have warm water at 8 PM without reheating.
• House cooling: If you have an air conditioner, cool the house at midday. Close curtains and doors to trap the cool air for the evening.

Batch Your Tasks

Instead of doing one load of laundry every day, do two or three on the best solar day of the week. Check the weekly forecast on Sunday and pick the clearest day for heavy-load tasks.

Similarly, batch your ironing. Iron everything for the week in one midday session instead of ironing one outfit each morning.

Cooking Strategy

If you have a gas stove, use it for evening cooking. If you cook electrically, shift your main meal preparation to lunchtime when solar production is at its peak. Evening meals can be simpler — reheated leftovers, salads, braai (which uses no electricity at all).

Track Your Usage Patterns

SolMate's forecast tool shows you exactly when conditions are best for running heavy loads. The Load Recommendations section tells you, appliance by appliance, whether now is a good time to run it. The Daily Planner breaks the day into hourly slots so you can build a schedule that matches your solar production.

Check the forecast each morning. On a clear day, you have the freedom to run everything midday. On a cloudy day, you might want to skip the non-essential loads entirely and conserve battery for the evening.

Over time, spreading your load becomes second nature. You stop thinking about it and just automatically throw the laundry in after breakfast, run the dishwasher at noon, and reach for the gas kettle after sunset. These small habits add up to thousands of kWh per year in solar self-consumption — and that translates directly to money saved.