Solar Batteries Explained — What Size Do You Really Need?

Introduction

When it comes to solar, batteries are everything. They’re the backbone of any reliable energy system—storing power for when the sun goes down or the grid goes offline.

But how do you choose the right one for your home or business in the Caribbean?

Let’s break it down.

1. Why Solar Batteries Matter?

In regions like Trinidad & Tobago, where blackouts are common, a battery isn’t optional—it’s essential.

Your solar panels generate power during the day. The battery stores the excess energy, ensuring your home runs smoothly through the night or during outages.

Without one, your solar setup is incomplete.

2. Understanding Battery Capacity (kWh)

Battery size is measured in kilowatt-hours (kWh)—the total energy it can store.

Here’s a quick guide:

Small Homes / Apartments → 3–5 kWh - Run lights, fans, Wi-Fi, and small electronics for several hours.

Medium Homes → 10–15 kWh - Keep fridges, TVs, and key appliances powered overnight.

Large Homes or Small Businesses → 20–30 kWh - Power full households or retail shops through multi-hour outages.

Commercial or Industrial Use → 50+ kWh - Maintain production or refrigeration during grid failures.

3. Lithium vs. Lead-Acid Batteries

Lithium (LiFePO₄):

10–15 year lifespan | 90% usable capacity | Low maintenance | Ideal for long-term ROI

Lead-Acid (AGM or Gel):

3–5 year lifespan | 50% usable capacity | Lower upfront cost, but higher total cost over time

Our Recommendation:

Choose lithium batteries for any modern solar setup—they’re safer, longer-lasting, and more efficient.

4. Backup Time & Load Planning

The easiest way to size your battery:

Add up your daily essential loads.

Example:

Lights (300W x 5h) = 1.5 kWh

Fridge (150W x 24h) = 3.6 kWh

Wi-Fi + TV (100W x 6h) = 0.6 kWh

✅ Total = 5.7 kWh/day → a 7–10 kWh battery is ideal.

5. Smart Pairing: Battery + Solar Generator

For most homeowners, pairing a battery with a solar generator or inverter offers flexibility—instant backup now, expandability later.

You can start small and scale into a full off-grid or hybrid system when ready.

Conclusion: Choose Storage That Matches Your Lifestyle

Whether it’s keeping the lights on during blackouts or lowering your monthly bill, solar batteries give you independence.

With the right size and chemistry, your system will serve you reliably for years to come.

Need help choosing the right battery size?