Inverter vs Conventional Generators: Which Should You Buy?

The Generator Decision That Actually Matters

Walk into any generator showroom and you’ll face a choice: inverter or conventional. The price difference is massive—sometimes double. But is an inverter generator worth the extra cash, or is it just marketing fluff?

I’ll be straight with you: it depends entirely on what you’re powering and where you’re using it.

Let me break down the real differences so you can make a sensible decision without getting blinded by sales patter.

What Actually IS an Inverter Generator?

The Technical Bit (Simplified)

A conventional generator produces AC power directly from the alternator. The engine speed determines the frequency—3,000 RPM for 50Hz in the UK. Fixed speed, fixed output, running at full blast whether you’re drawing 100W or 2,000W.

An inverter generator produces raw AC power, converts it to DC, then inverts it back to clean AC at exactly 50Hz. Sounds mad, doesn’t it? But this extra step lets the engine speed vary with load.

Drawing 200W? Engine slows down. Drawing 2kW? It speeds up. That’s where the magic happens.

What This Means in Practice

Clean Power Inverter tech produces incredibly stable power. Total Harmonic Distortion (THD) under 3%. That’s “computer safe” power—won’t fry your laptop or glitch your sensitive electronics.

Conventional generators? THD varies from 6-12%. Usually fine, but I wouldn’t plug in anything expensive without a surge protector.

Variable Speed Operation This is the game-changer. Conventional generators run at 3,000 RPM constantly. Inverter generators idle down when you’re drawing minimal power, saving fuel and reducing noise.

You’ll get 8-10 hours from a tank instead of 4-6 hours. Over a year, that adds up.

The Noise Factor: Why Your Neighbours Care

Let’s talk decibels, because this is where inverter generators absolutely dominate.

Real-World Noise Comparison

That’s not a small difference. That’s the difference between “complaints from three doors down” and “didn’t realise it was running.”

Our Honda inverter range runs so quietly you can have a normal conversation stood next to one. Try that with a conventional site generator.

Power Quality: Does It Really Matter?

Sensitive Electronics (The Honest Answer)

Modern electronics have switching power supplies. They’re pretty tolerant of rough power. Your phone charger? Fridge? LED lights? They’ll run fine on either type.

But if you’re powering:

• Laptops and computers
• Medical equipment
• Audio/visual gear
• Variable speed tools
• Anything with a microprocessor

You want clean power. Dirty power causes:

1. Premature component failure
2. Data corruption
3. Unexpected shutdowns
4. Reduced equipment lifespan

One burned-out laptop motherboard costs more than the generator price difference.

The Camping/Leisure Test

Take a conventional generator camping. You’ll power the site. Everyone will know you’re there. Some will hate you for it.

Take an inverter generator from our leisure range. You’ll blend in. Campsite wardens won’t give you dirty looks.

I know which I’d choose.

Fuel Efficiency: The Long-Term Cost

This is where inverter generators pay back their premium.

Annual Running Cost Comparison

Scenario: Powering a small office during frequent outages (200 hours/year)

Conventional 5kW Generator

• Fuel consumption: 2.5 L/hr at all loads
• Annual fuel: 500 litres
• Cost at £1.50/L: £750/year

Inverter 5kW Generator

• Fuel consumption: 0.9 L/hr at 25% load, 2.1 L/hr at full load
• Average consumption: 1.4 L/hr
• Annual fuel: 280 litres
• Cost at £1.50/L: £420/year

Annual saving: £330

The inverter generator pays for its price premium in 3-4 years. After that, you’re £300-400 better off every year.

Portability and Practical Use

Weight and Size

Inverter generators are ridiculously lighter. A 2kW inverter weighs 20-25kg. A conventional 2kW? Try 40-50kg.

That’s the difference between “I can lift this myself” and “I need help getting it in the van.”

For mobile applications—camping, trade shows, outside catering, location filming—inverter wins hands down. Our Yamaha inverter range is particularly popular with mobile caterers for this reason.

Parallel Capability

Many inverter models can link together. Got one 2kW inverter? Buy another identical unit, connect them with a cable, and you’ve got 4kW.

Conventional generators don’t do this. You’re stuck with the capacity you bought.

Where Conventional Generators Still Win

I’m not saying inverter generators are always better. They’re not.

High Power Requirements

Need 10kW+? Inverter technology gets expensive fast. Really expensive. A 10kW inverter generator costs 2-3 times more than a conventional equivalent.

For standby home backup or commercial installations, conventional generators from CAT, Cummins, or FG Wilson make more financial sense.

Check our standby generator options for permanent installations.

Continuous Heavy Load

Running a workshop all day? Powering multiple high-draw tools continuously? Conventional generators handle sustained heavy loads better.

Inverter generators excel at variable loads. Constant full-power operation negates most of their advantages.

Budget Constraints

If £300 is your limit, you’re buying conventional. A decent inverter generator starts around £600-800 for 2kW.

Sometimes you just need power. Any power. Right now. Conventional delivers.

Making Your Decision: The Quick Checklist

Choose Inverter If:

1. You’re powering computers, phones, or sensitive electronics
2. Noise matters (camping, residential areas, events)
3. You need portability (under 30kg is desirable)
4. You want better fuel economy
5. Power requirements are under 5kW
6. Load varies significantly during use

Choose Conventional If:

1. You need 10kW or more
2. Budget is tight (under £500)
3. You’re running constant heavy loads
4. Noise isn’t a concern (workshops, farms, construction)
5. You need three-phase power
6. It’s for standby/emergency backup only

The Brands That Matter

Quality varies wildly in the generator market. Stick with proven manufacturers.

For Inverter: Honda and Yamaha set the standard. Reliable, well-supported, hold their value.

For Conventional: SDMO, Pramac, and Perkins offer excellent value. Industrial quality without the premium price.

Browse our full generator brands to compare specifications across ranges.

Final Verdict

There’s no universal “best” generator type. There’s only the best generator for your specific situation.

Small, mobile, quiet, efficient? Inverter.

Big, powerful, budget-conscious, permanent installation? Conventional.

Most people with portable power needs under 5kW should buy inverter. The extra cost pays back through fuel savings and actually being able to use it near other humans.

Most people needing serious backup power over 10kW should buy conventional. The cost difference at higher capacities doesn’t justify the marginal benefits.

And if you’re still unsure? That’s what we’re here for.