11 Douglas RoadKingswoodBS15 8NH

Phone Number: 01172 541 059

What Size Generator Do I Need?
Bristol, Bath and Cardiff

When you are hosting an event or celebration, one of the questions often asked is: What Size Generator Do I Need? 

Bristol Event Generators offer generator hire for Bristol, Bath, Cardiff and the surrounding areas. Find out more about which size generator is right for you.

What Size Generator Do I Need? Bristol, Bath and Cardiff

Hiring a generator can be confusing and overwhelming, particularly if it's your first time. 

What is the right size generator for me? What are Inverter generators? What do I need along with the actual generator?

Bristol Event Generators are experienced experts on hand to answer any questions you may have.  Our comprehensive hire service can help your event organisation run smoothly, so you have no need to worry. 

At Bristol Event Generators, our specialist hire fleet of generators and vehicles can hire across the South West of England and South Wales.  

We have a wide range of models from recognised and trusted brands, suitable for various sized events, from a small marquee wedding to a weekend music festival. 

Are you looking for generator hire in Bristol and the surrounding areas, call 01172 541 059 today.

We can also respond to an emergency such as power outages to provide an emergency power source. 

Our emergency response team is available 24 hours a day on {phone_numer}.  

Our staff are continuously trained to the highest industry standard and are knowledgeable about our specialist fleet of hire generators. 

Upon delivery, we can complete the set-up for you and brief a responsible person on the generator's operation and features.  Our smaller, compact range of generators can be easily transported to an alternate location on the site if required.

How to calculate what size generator is best for me?

To determine what size generator you will need, you will need to list all the appliances you want to run on it. If this is for your home, list the devices you want to power in the case of a power outage. This list might include your freezer, lighting etc.  


The next step is to calculate the total power requirements for the appliances in your list. 'Starting wattage' is the amount of power needed to start a device, with motorised items like air conditioners requiring more power than others. 'Running wattage' is the amount of power necessary to keep your appliance going after it has started.    

For example, a typical 10,000 air conditioner uses 2,200 of starting wattage. After this preliminary starting, it's energy consumption falls. The air conditioner would then need a generator with a regular supply of 1,500 running watts. 

We recommend that you consider both of these numbers when selecting the size of the portable diesel fuel generators you require, as it will need to have sufficient starting wattage and running wattage for your appliance.    

The next step is to choose a diesel generator that is slightly larger than what you require. It is always better to hire a generator that is too big than one that is too small. 

Ensuring you have extra power to work with means your portable generator will not cut out through overloading. Additionally, running a generator at full capacity will significantly shorten its lifespan.

Furthermore, a diesel generator running at maximum power can be incredibly noisy, especially if you plan to use it when camping or in quiet places. So, to be safe, for example, if you require 1,600 running watts, hire a diesel generator that can provide at least 1,800.   

Are you looking for generator hire in Bristol and the surrounding areas, call 01172 541 059 today.


What size generator do I Need to Run the Whole House?

Most essential house appliances, such as lighting and freezers, can be run from a generator with a 5,000 to 7,500-watt rating. A portable generator rated at the higher end of this scale can run most of your appliances at once. 

Checking all of the labels on your devices to see what wattage they require will help you when choosing a generator of the right size.  

However, one crucial question is whether you wish to power your whole house or just your essential devices? If you only want a diesel generator for emergencies, then smaller sizes will suit you best. It would be overly expensive for you to run all of your items if you do not need to. 

DJ Equipment2,000 - 3,000Outdoor Lighting2,000 - 3,000
Television Set75 - 200
Hot Water Service2,500 - 3,000Toaster250 - 1,250
Iron900 - 1,200Washing Machine500 - 3,000
Kettle / Jug800 - 1500Air Conditioner (Non-inverter)1,000 - 2,500
Lights25 - 200Domestic Water PumpSee Electric
Motor below
Radio60Electric Motor
0.25 hp*
0.5 hp*
1 hp*
2 hp*

Radiator1,000 - 2,500Welder, 140 Amp(Non-inverter)5,000
Refrigerator100 - 8009"Angle Grinder2,300

How to calculate the wattage required?

The calculation for the wattage you require is relatively straight forward.  

You take the wattages for each of your devices together, multiply the wattage by 3 if the item has an induction motor, then add 20% of the total wattage to be safe. Altogether that equals the wattage of generator you require.  

 For example, To run a 250W slow cooker and a 650W drill, the equation would be: 

 650W x 3 = 1950W 

 1950W + 250 = 2,200W 

 2,200 + 20% = 2640W 

Silent Generator Hire For Weddings

Do you want to hire a silent generator for a wedding? 

One of the most common reason to hire a generator is a temporary power source at an outdoor wedding.  Functions like this are usually required for outdoor wedding receptions for caterers and entertainment at rural locations. 

Bristol Event Generators have powered countless weddings across the South West, and we would be more than happy to recommend a suitable generator model for your needs. For an evening of entertainment, our compact, domestic generators are perfectly suited for the job. Their design helps them to run quietly so that they do not disturb the atmosphere of the evening. 

 If you are holding an event in Bristol, Somerset or Wiltshire, contact Bristol Event Generators for silent generator hire. We regularly service our generators to ensure they provide reliable performance for your special night.  

 We understand that wedding planning can be stressful, which is why we aim to provide the most efficient and straightforward generator hire service possible.   

Silent Generator Hire For WeddingsWedding generator ready for hire

Are you looking for generator hire in Bristol and the surrounding areas, call 01172 541 059 today.

Home use or professional use?

When considering a generator for home use, you should think about hiring smaller sized ones that you can use occasionally. If you would use it as power tools or as a back-up power supply, you won't require that big of a generator to do so.  On the other hand, if you want to run a generator daily or for work, then a larger size will be best. Larger wattages mean more power so that you can run larger generators for longer. 

100kVA Generator Hire Price

Bristol Event Generators is not a large, nationwide chain that likes to confuse our customers with technical jargon. We offer the best generator hire price in Bristol. If you have any questions regarding our product or service, please don't hesitate to get in touch, and we will always try our best to help. 

 Our generator sizes range from a compact 6kVA to a generous 135kVA. As a general rule of thumb, the size of the generator you need can be calculated by what you need to power and where. Our team of knowledgeable engineers can help you decide which size generator is the best for your bespoke requirements.   

Are you looking for a silent generator hire in Bristol, Cardiff, Bath or Gloucester? Our hire terms are flexible with a fair, competitive rate, even for our large commercial 100kVA generator hire. 

A compliant electrician thoroughly tests all of our generators before delivery. Additionally, all of our generators have numerous safety features for maximum peace of mind. 

Contact us

Complete the form below to discuss your outdoor or temporary power needs. We are happy to discuss how silent generator hire can benefit you. 

We can supply 6kVA to 135kVA generator hire for outdoor weddings, festivals, events, construction and more.

Call our 24 hour number 01172 541 059.