How to Run 1 Fan and 2 Lights on Solar: Cost, Battery Size and Savings

 

Introduction

Running one fan and two lights on solar is one of the most common small solar projects. It is simple, affordable, and useful during power cuts, in a small room, or in a home that wants to cut evening electricity use. You do not need a large rooftop system or a huge battery to make it work. This guide shows, step by step, how much energy they use, what panel and battery size you need, what inverter to choose, what the system might cost, and how much you could save. All costs are general estimates only, not guarantees, because prices vary by country, brand, and installation.

How Much Energy Do 1 Fan and 2 Lights Use?

Wattage varies, so check labels on your own devices. A typical ceiling fan uses about 50 to 75 watts, a smaller pedestal fan 40 to 60 watts, and an LED light 9 to 15 watts. For this guide, use one 60-watt fan and two 12-watt lights: 84 watts together. Run for five hours, that is 420 watt-hours. For three hours, it is 252 watt-hours. For eight hours overnight, it rises to about 672 watt-hours. Decide realistic hours first and size for that, not a best-case day, because a system sized for five hours will struggle if you later run the fan all night.

What Size Panel Do You Need?

For 420 watt-hours over five hours, with roughly four good sun hours, a 150-watt panel is a sensible starting point, and a 200-watt panel gives useful margin for cloudy days and losses. For three hours a day, about 252 watt-hours, a 100-watt panel can be enough in good sun. For eight hours, about 672 watt-hours, you may need 250 to 300 watts. Choose a slightly larger panel rather than a bare minimum, and face it toward the sun with little shading. A larger panel charges faster, but it does not by itself run the fan longer at night — that is the battery's job.

What Battery Size Do You Need?

For five hours at 420 watt-hours, a 12-volt battery of about 50 to 60 amp-hours is a practical choice with a lead-acid battery, allowing for losses and not draining it fully. A lithium battery can be smaller for the same usable energy, often around 35 to 50 amp-hours, because it can be used more deeply. For eight hours, about 672 watt-hours, look toward 80 to 100 amp-hours lead-acid, or 60 to 80 amp-hours lithium. Always match the battery voltage and type to your charge controller and inverter, and leave margin for a cloudy day. If night use matters most, spend more on the battery before buying a bigger panel.

Do You Need an Inverter?

It depends on your fan and lights. If they are 12-volt DC devices, you may run them directly from the battery through a controller, without an inverter. If they are normal mains AC devices, you need an inverter to change battery DC power into AC power. For an 84-watt load, a 200 to 300-watt inverter is usually enough, with margin for the fan's start-up surge. A pure sine wave inverter is safer for motors and electronics than a modified sine wave type. Do not oversize the inverter far beyond need, because a large inverter can waste power on standby.

Step-by-Step Setup Guide

Step 1: Check Your Devices

Note the wattage on the fan and lights, and decide how many hours they will run each day.

Step 2: Choose the Panel

Pick a panel size from the guide above, with a little extra margin, and place it in good sun with little shade.

Step 3: Choose the Battery and Controller

Match the battery to your night use, and use a charge controller rated for your panel and battery type.

Step 4: Add the Inverter If Needed

For mains devices, add a correctly sized pure sine wave inverter; for DC devices, you may not need one.

Step 5: Connect Safely

Connect panel to controller, controller to battery, and battery to inverter or load, following the product manuals and using correct fuses and wiring. If you are unsure about wiring, ask a qualified installer.

Step 6: Test and Track

Run the fan and lights in the evening, watch how long the battery lasts, and adjust use or size if it runs out too early.

Cost Breakdown: Estimates Only

As a rough guide only, a small setup might cost: panel $80 to $180, battery $70 to $200, charge controller $20 to $50, inverter if needed $40 to $120, plus cables, fuses and mounting $30 to $80. Total is often $240 to $630, before installation help. Prices vary widely by country and quality, so get local quotes before buying.

How Much Can You Save?

If you run 420 watt-hours a day from solar instead of the grid, that is about 12.6 kilowatt-hours a month, or about 151 kilowatt-hours a year. At 20 cents per kilowatt-hour, that is about $30 a year; at 40 cents, about $60 a year. Savings are higher where electricity is expensive or power cuts are common, because the value is also comfort and backup, not only the bill. A small system may take several years to pay for itself, so judge it on reliability as well as savings.

Common Mistakes to Avoid

Do not buy the cheapest battery without checking its type and usable capacity. Do not skip the charge controller. Do not run a large television or fridge on a system sized only for a fan and lights. Do not place the panel in shade. Do not ignore fuses and safe wiring.

Frequently Asked Questions

Can I run 1 fan and 2 lights on a 100W panel?

Yes, in good sun for a few hours a day. A 100-watt panel can cover about 252 watt-hours for three hours, but for five hours or cloudy days, a larger panel is safer.

How long will the battery last each night?

It depends on battery size and use. A well-sized battery for five hours should last the evening, but running the fan all night needs a larger battery.

Can I add a television later to the same system?

Only with a larger panel, battery and inverter. A television adds a large load, so size the whole system again before adding it.

Is solar for just a fan and lights worth it?

Yes, if you value backup during cuts and lower evening grid use. It is a low-cost way to start with solar, even if payback takes time.

Conclusion

Running 1 fan and 2 lights on solar is a practical first solar project. Start with your real daily hours, choose a panel and battery with margin, add an inverter only if your devices need it, and install it safely. With the right size, you get light and cooling when you need them, and a useful step toward lower electricity use.