The Ultimate Buyers Generator Guide
When buying a generator, it’s important to ensure you get the right one for your needs. Whether you’re using it as a backup power source during power outages, for your mobile business, events or camping, having a generator that meets your specific requirements is essential. With so many different types and sizes of generators available, it can take time to know which one is best for you. To help you make an informed decision, we’ve put together a guide outlining the key factors and parameters to consider when buying a generator.
What are your Requirements?
Purpose
When choosing a generator, it’s essential to consider the intended application. Will it be used for domestic purposes, such as backup power for homes, or for industrial purposes, such as powering a factory? Knowing the specific use of the generator will help narrow down your options.
Power Output
To ensure the generator can handle the load you need, it’s essential to conduct a power analysis. Overloading a generator can cause damage to your appliances or the generator itself, so it’s important to choose one with the appropriate wattage. Remember that most appliances require a higher current when they start, known as a surge, so your generator should have enough spare capacity to handle this.
Fuel Type
It’s also important to consider the fuel type of the generator, as this can impact the fuel cost. Options include diesel, LPG, and petrol generators, each with fuel efficiency and cost.
Type of Load
The load the generator will be powering also plays a role in the selection process. Will it be used for heavy-duty equipment or sensitive electronics? If the latter is the case, an inverter generator may be necessary to provide a higher-quality AC current and protect electronic devices.

Electrical Usage
When it comes to generators for domestic use, there are a few different options to choose from. Portable generators are great for running smaller appliances, such as drills, saws, and lights, but they may need to be more powerful to supply energy to an entire house. They typically range in power output from 1 KW to 15 KW and are ideal for construction or home improvement projects without electricity.
Another option for residential use is a whole-house or standby generator. These generators are designed to power all appliances in case of failure. They have a higher power output, ranging from 7 KW to several hundred KWs, and allow for complete independence from the electrical grid. With a standby generator, you can continue to run lights and appliances during a power outage.
Backup Power with a Transfer Switch
When installing a generator, it’s essential to consider a transfer switch. A manual transfer switch allows you to switch between utility power supplied by the grid and backup power with the push of a button. While easy to use, you must manually locate the switch during a blackout.
An automatic transfer switch (ATS) eliminates this step by automatically sensing a power outage and switching to backup power with minimal delay. When utility power is restored, the ATS switches back to grid power and turns off the generator.

Power Requirements
It is crucial to determine the power needed to run your appliances. The power requirements for each device can typically be found on its label or manual, measured in kVA. Remember that some devices may also require additional starting kVA, which can be calculated by multiplying the device’s watts by 3. When purchasing a generator, choosing one with a KVA rating of at least 20% greater than your estimated power needs is essential.
For example, if your estimated power needs are 6000 watts, you should look for a generator with a KVA rating of at least 7200. It is important to note that the watts mentioned below are approximate, and you should check the equipment label to get an exact number. It’s also essential to evaluate your needs at the home or commercial level to get a proper assessment.
Camping
Motorhomes
Caravans
Mobile catering
Motor sports
Lighting
Low power mains back up
Low power heating
Emergency service vehicles
Off grid homes
Power tools
Charging batteries
Mobile catering
Motor sports
Lighting
Low power heating
Domestic mains back up
Welfare cabins
Building sites
Industrial units
Telecoms
Small marquees
Railway works
Road works
Light manufacturing facilities
Emergency services support
Off grid solar systems
Lighting
Industrial heating
Industrial Mains back up
Building sites
Industrial
Telecoms
Powering machinery
Cranes
Light manufacturing
Marquees
Music events
Fairground rides
Farming/ agriculture
Industrial heating
Industrial mains back up
Large domestic back up
Building
Industrial
Powering machinery
Cranes
Food manufacturing
Brewery’s
Bakery’s
Large marquees
Music festivals
Small medical facilities
Farming/ agriculture
Meat production
Dairy’s
Forestry
Fairgrounds
Schools
Military communication
Boats
Quarrying
Large industrial heating systems
Heavy industrial mains back up
Network distribution support
Food manufacturing
Brewery’s
Hospitals
Bakery’s
Farming/ agriculture
Data centres/ storage
Fairgrounds
Military support
Airports
Large music events
Motor sport
Boats/ ships
Meat production
Dairy’s
Government/ council buildings
Quarrying
Ports
Cable laying
Wind farms
Oil and gas
It is important to remember that these are just estimates, and you should check the equipment label for actual power consumption.
Once you have determined the power needs of your appliances in watts, you can select a generator that meets those requirements. Generators are typically rated in KVA or KWs. To convert watts to KWs, divide the total by 1000. However, to convert watts to KVA, you first need to convert to KWs and then divide by 0.8, representing the power factor, as shown below…
- To convert Watts (W) to KiloWatts (kW), divide by 1000 – Eg. 1000W = 1kW
- To convert KiloWatts (kW) to Kilo-volt-amps (kVA) divide by 0.8 – Eg. 1000W = 1kW = 1.25kVA

Choosing from LPG, Diesel and Petrol Generators
In the UK, certain brands of generators are particularly popular, such as Honda, Hyundai, Pramac and Linz. When choosing a generator, it’s also important to consider the type of fuel it uses. LPG generators are powered by liquid propane or natural gas and are popular as portable or standby home generators.
They are cheaper to operate and are considered more environmentally friendly. Diesel generators are typically preferred for commercial applications due to their larger size and longer run time. They also have good fuel economy, making them a cost-effective option.
Petrol generators are suitable for domestic and commercial use and have power outputs ranging from 1 KVA to 10 KVA. Petrol is the most widely available fuel, but keep in mind that it can go bad if stored for extended periods.
Silent Generators
Many people prefer quiet generators, which produce less noise than traditional generators. Silent generators have noise levels similar to central air conditioning units. They are popular among campers, small business owners, large enterprises, and homeowners who want a reliable backup power source. With long run times, they can keep power supplied during extended power outages.


Why Choose Bellwood
Generators can provide power for extended periods, even when the main power grid is down for weeks. Investing in a generator can also help keep you informed during emergencies, as you can power televisions and charge laptops.
Bellwood Rewinds offers durable generators for both domestic and commercial use. We are a reputable supplier of generators in the UK and carry a wide selection of top-quality generators from top brands. Our generator selector tool and first-time buyer’s tool can assist you in finding the perfect generator for your needs.
Our customer service team can provide personalised consultation if you need additional support. Our technical experts will work with you to understand your specific needs and ensure you find the right product. Contact us to learn more.