Best Diesel Generators: Top Picks and Buyer’s Guide

At Grounded Electric, we help homeowners and businesses choose the best diesel generator for backup power. Robert “Bobby” Mulholland brings 30 years of field work, and Barret Abramow manages projects with care.

Our team ensures that clients receive reliable power solutions tailored to their specific needs. This guide reviews the best diesel generators, from compact models to large 30kW units.

Key Takeaways

• • The best diesel generator depends on needs, from portable units to 30kW sets for businesses.

• • Top brands, such as Cummins, Caterpillar, Perkins, Generac, and MTU, are renowned for their reliable diesel generators, which consistently deliver strong performance.

• • Important buying factors include power output, fuel efficiency, engine type, noise, and maintenance costs.

• • A 15kW diesel generator can run a mid-sized home, while a 30kW unit can power restaurants, shops, or offices.

• • With routine care and trusted engines, diesel generators can last 20 years or more.

Top Diesel Generator Brands

Several companies are trusted worldwide for diesel generators. They offer strong designs, a wide range of models, and dependable power.

• • Cummins – Industrial-grade with good fuel economy.

• • Caterpillar (CAT) – Strong commercial diesel generator sets.

• • Perkins – Durable Perkins engines for mid-sized use.

• • Generac – Popular for homes and portable diesel models.

• • MTU (Rolls-Royce) – High-performance units for tough needs.

• • Yanmar – Compact, fuel-efficient designs.

• • Mitsubishi – Diesel engine tech for reliable power.

• • Deutz – Efficient engines across generator sets.

• • Doosan – Affordable but reliable for businesses.

• • Volvo Penta – High quality, strong fuel economy.

Best Diesel Generator Brands and Models

What Is the Best Portable Diesel Generator?

Portable diesel models offer flexible and reliable power for on-the-go use or short-term applications. The best portable diesel generator balances fuel efficiency with steady power output.

Our Pick
Generac XD5000E — a strong portable unit built for moving around, offering good power output and durability.

Best Diesel Generator for Home Backup

The best diesel generator for home backup ensures that lights and appliances continue to run during power outages. 

Homes often use 10kW to 20kW models. These diesel generators for the home save fuel and run longer on diesel fuel.

Our Pick
Generac Protector 15kW Standby — automatic standby mode, solid 15 kW output, good for keeping lights, HVAC, and appliances running during blackouts.

Best Diesel Generator for RV Travel

RV owners need small, quiet, portable diesel units. A compact portable diesel generator can power AC, lights, and small appliances on trips.

Our Pick
Yanmar YDG Series — compact and quiet, suitable for RVs that need AC, lights, and small appliances while traveling.

Best 30kW Diesel Generator for Businesses

The best 30kW diesel generator is strong enough for small shops, restaurants, or offices. It provides reliable power output for key systems. 

Many use Perkins engines, which are renowned for their longevity and excellent fuel economy.

Our Pick
MTU 1600 Series — strong performance, built for continuous use, ideal for small shops or restaurants with high demand.

Best 15kW Diesel Generator for Mid-Sized Homes

The best 15kW diesel generator can handle larger homes. It operates HVAC systems, appliances, and electronics with consistent performance.

Our Pick
Generac Protector RD01525 (15 kW, diesel, 1800 RPM) – residential standby unit suited to mid-sized homes; supports 120/240V single-phase and includes remote monitoring options. Many homeowners also wonder, are Generac generators worth it?

Best Compact Diesel Generator Options

The best compact diesel generator is both lightweight and steady. It works well for contractors, vendors, or anyone who needs easy transport.

 

Yanmar YDG5500W-6EI — 5,500 watt portable diesel generator, 120/240V single phase, air-cooled, recoil/electric start. 

Top Models Compared: Features and Prices

• • Power output – Pick a size that matches your needs.

• • Fuel efficiency – Less fuel use saves money.

• • Noise levels – Quiet units fit homes or RVs.

• • Build quality – Choose high-quality diesel-powered parts.

Notable Diesel Generator Models

• • Generac XD5000E – Portable with solid output.

 

• • Caterpillar 3516 – High-performance commercial unit.

• • Perkins 400 Series – Fuel-efficient, reliable mid-size.

• • MTU 1600 Series – Runs nonstop for industries.

 

• • Yanmar YDG Series – Compact and quiet for homes and RVs.

Quick Comparison of Diesel Generators

• • 10kW Portable Diesel Generator – Good for partial home backup.

• • 15kW Diesel Generator – Runs mid-sized homes with HVAC.

• • 30kW Diesel Generator – Powers small businesses.

• • Compact Portable Diesel – Easy for contractors or RVs.

• • Industrial Diesel Generator Sets – Top-tier power for large sites.

How to Choose the Right Diesel Generator

Key Features and Specifications

Check power output, runtime, cooling, and ease of care. Reliable diesel generators should match your home or business.

Diesel Engine Options to Consider

Engines matter most. Perkins engines are trusted for fuel economy and long life. Mitsubishi, Deutz, and Doosan also provide reliable power generation.

Most Fuel-Efficient Diesel Generators

Fuel efficiency lowers costs. Models with advanced diesel engine design and good fuel economy ratings give better value.

What Is a Tier 4 Diesel Generator?

Tier 4 diesel generators meet strict rules for emissions. They cut harmful exhaust and work for both residential and commercial use.

Maintenance Tips to Extend Generator Lifespan

• • Change filters and oil often.

• • Inspect the diesel engine before use.

• • Store only clean diesel fuel.

• • Routine care keeps reliable diesel generators running for many years.

Cost of Diesel Generators

Price Range by Size and Power Output

In New Jersey, diesel generator costs depend on size. Small, portable units with a capacity of around 10 kW typically range from $9,000 to $14,000.

Mid-sized home backup models, ranging from 15 to 20 kW, typically cost between $12,000 and $16,000, including installation. Larger commercial units, typically around 30 kW, typically run between $17,000 and $19,000.

Practical Examples of Generator Use

A 15kW diesel generator can run a 2,500-square-foot home with HVAC and lights. A 30kW diesel generator set can support a restaurant or office. Compact diesel-powered models work well for food trucks or contractors.

Long-Term Maintenance and Operating Costs

Costs include diesel fuel, service, and part replacements. High-quality models last longer and save money with better fuel efficiency.

Used vs. New Diesel Generators

Used diesel generators for sale can save money at first, but they need more care. New models offer warranties, advanced technology, and reliable power.

Where to Buy Diesel Generators Online or Locally

Buy from certified dealers, online stores, or local experts like Grounded Electric. Barret Abramow can guide buyers to the right choice.

Finding the Best Diesel Generator

The best diesel generator depends on size, fuel efficiency, and use. With help from Robert “Bobby” Mulholland and Barret Abramow at Grounded Electric, buyers can trust in high-quality and reliable diesel generators for home or business.

For expert guidance and a custom quote, call Grounded Electric today to discuss your power needs.