Power cuts are inconvenient at best and disastrous at worst. Whether you’re a homeowner worried about a winter blackout, a small business owner needing backup power, or someone planning a festival or outdoor event, having the right generator can make all the difference. But how do you decide between a standby generator and a portable one? Both do the same basic job — providing electricity when you can’t get it from the mains — yet they’re very different in design, cost and how they fit into your daily life or business operations.
Understanding the key differences will help you make a decision that matches your needs and budget while giving you peace of mind when the lights go out.
What Is a Standby Generator?
A standby generator is designed to sit permanently outside your home or business, ready to spring into action the moment there’s a power failure. Connected directly to your electrical system, these units monitor your mains supply. If the power goes off, the generator kicks in automatically, often within seconds, and keeps your essential circuits running.
These generators are typically fuelled by diesel, natural gas or LPG. They can run for days at a time as long as they have fuel, making them especially useful for areas prone to frequent or lengthy power outages. Some larger homes and critical businesses, like care homes, surgeries and shops with cold storage, rely heavily on standby generators to ensure operations continue without interruption.
What Is a Portable Generator?
A portable generator does exactly what its name suggests — it’s a compact, moveable power source you can bring out and fire up whenever you need it. These generators aren’t hard-wired into your home’s electrical system. Instead, you plug appliances directly into the generator’s sockets or, for more advanced models, into a dedicated transfer switch that powers part of your house.
Portable generators are powered by petrol or diesel and come in a huge range of sizes. Small units might power a few lights and a fridge, while larger ones can keep essential circuits running in a medium-sized house. Outside of home backup use, they’re popular for building sites, food trucks, camping trips and outdoor events like farmers’ markets or community fairs.
Cost and Installation: What to Expect
One of the biggest differences between standby and portable generators is the upfront cost. Standby generators are a significant investment. Not only is the unit itself expensive, but professional installation is essential. The process involves connecting the generator to your property’s electrical system and fuel supply and setting up an automatic transfer switch. This ensures the switch from mains to backup power happens seamlessly. It’s a job that needs a qualified electrician and, for gas units, a registered Gas Safe engineer.
Portable generators are far cheaper to buy. There’s no complex installation — you can keep the generator stored in a shed or garage and wheel it out when needed. As long as you follow basic safety advice, you can set it up yourself. However, powering your whole house with a portable unit is rarely practical. Many people use them to run extension leads to essential appliances rather than wiring them into the building’s electrical system.
Reliability When You Need It Most
If you’re in an area where blackouts are rare or short-lived, a portable generator might be enough. It gives you flexibility and costs far less than a permanent setup. You have to remember, though, that portable generators need to be manually set up and started when the power fails. You’ll also need to manage fuel storage safely and maintain the generator so it’s ready to run when you need it.
Standby generators, on the other hand, offer true ‘fit and forget’ peace of mind. They start automatically, even if you’re not at home. They’ll keep vital systems like heating, lighting, refrigeration and medical equipment running. For businesses, they’re often essential for avoiding lost revenue, spoiled stock or equipment damage.
Fuel Considerations
Most portable generators are petrol-powered, although diesel models are available too. Petrol is easy to get but has a shorter shelf life, which means you need to rotate your fuel supply regularly. Storing petrol safely at home also has limits under UK law. Diesel lasts longer but can be less convenient for very small domestic models.
Standby generators more commonly run on diesel, natural gas or LPG. If you already have a mains gas supply, a gas standby generator means you don’t need to worry about storing fuel at all. Diesel standby sets are popular for commercial and rural use, but you’ll need an appropriate fuel tank installed and maintained in line with local regulations.
Power Output and Usage
The size and power output of your generator should always match your needs. Portable generators come in a wide range of capacities, from just enough to run a kettle to units that can handle the start-up surge of large appliances. The catch is that you have to choose what to power, especially during extended outages.
Standby generators are sized to cover more. You can choose whether to power the whole building or just essential circuits. This flexibility is especially useful for larger homes, businesses and farms where losing heating, IT systems, or security could have serious consequences.
Noise and Location
Noise can be an issue with generators. Portable petrol generators can be noisy, which is fine on a building site but less ideal for a peaceful residential street. Many modern models use inverter technology to run more quietly, but they still produce a noticeable hum.
Standby generators are designed for permanent outdoor installation, usually positioned away from windows and neighbours. Many are built into soundproofed enclosures that keep the noise to a minimum, which is important if the unit needs to run for several hours or days.
Maintenance Requirements
Both standby and portable generators need looking after. A portable unit should be run periodically, fuel levels checked and oil changed according to the manufacturer’s schedule. It’s also good practice to test your setup every few months to make sure it’s still reliable.
A standby generator is more of an investment in this regard too. Regular servicing of your generator is a must, especially for larger diesel models. Many businesses and homeowners take out a maintenance contract that includes routine inspections, test runs and fuel checks. The benefit is that when a power cut does strike, you know your generator is in peak condition.
Which Is More Eco-Friendly?
Neither option is truly green, but some choices are better than others. A portable petrol generator will emit more carbon dioxide per litre of fuel than a natural gas standby generator, for example. Diesel models, whether portable or fixed, produce particulates and nitrogen oxides that affect air quality.
The fuel source, efficiency and how the generator is used all play a role. Some modern standby generators can run on biofuels or renewable LPG, helping to reduce their carbon footprint. Portable generator technology is also improving, with inverter generators using fuel more efficiently and producing cleaner power for sensitive electronics.
Thinking About Safety
Safety should always be a priority. Portable generators must be used outdoors and kept well away from windows and doors to avoid carbon monoxide poisoning. They also need to be operated on level ground and kept dry to avoid electrical hazards.
Standby generators are permanently installed with ventilation and weather protection built in. They’re generally safer for families and staff because they start automatically and don’t require refuelling in the middle of a storm.
Finding the Best Fit for You
Deciding between a standby generator and a portable one is really about how much power you need, how often you expect to use it, and how much convenience and security you want.
If your power cuts are rare and short, a portable generator can be a cost-effective insurance policy that covers the basics. It gives you flexibility too — you can take it camping, lend it to a neighbour or use it on a project away from home.
If you need uninterrupted power for vital systems, or if an outage would lead to financial losses or safety concerns, a standby generator makes more sense. It’s an investment in long-term resilience, and it removes the hassle of setup and manual operation when you least need the extra stress.
The Power to Keep Going
Choosing the right generator means thinking through your needs carefully, both now and in the future. Whether you pick a portable model you can wheel out at a moment’s notice or a permanent standby unit that watches over your home or business silently, you’re investing in peace of mind.
Power cuts may be beyond your control — but with the right backup in place, you can carry on with far less worry when the unexpected happens.
