Water heating is one of the most energy-consuming activities we carry out in our homes. According to the Department of Energy, water heating accounts for at least 14% of our home’s utility bills and 20% of energy use.
Choosing the best type of water heater for your needs is crucial if you’re trying to monitor your energy costs closely. The less energy your heater uses, the more you save on your utility bill.
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Is it cheaper to heat water with gas or electric?
There are usually two options to consider when buying a water heater—gas or electric. Before picking either of them, you need to consider some factors. Most people consider a heater’s cost over anything else, while others also consider efficiency, energy consumption, capacity, safety, and installation. Needless to say, the second approach is the go-to way.
This article will talk about gas and electric water heaters, how much energy they consume, and which is the better option. Both gas and electric water heater installation should be carried out by gas technicians and qualified electrical experts, respectively. US residence can speak to professionals like Chicago Electrician’s for further advice.

Gas-powered water heating
Gas water heaters are very common. They exist as tanks that heat water using a natural gas or propane gas-powered burner. The burner sits at the bottom of the tank, where it heats up and boils the water at the bottom before progressing to the top. Gas heaters usually have a discharge tube at the top that draws water up.
Gas water heaters are cheaper to use than electric heaters because, on average, gas is cheaper than electricity. You’ll spend more money using an electric heater than a gas heater. Gas water heaters also heat water faster than electric units and are helpful in a power outage.
But before you choose to get a gas water heater, know that they’re less energy efficient than electric water heaters. They may be cheaper and work faster, but they waste a lot of energy. This energy waste is due to heat loss that happens during heating cycles.
During a heating cycle, gas-powered water heaters give off byproducts like carbon dioxide and release energy along with it.
Gas water heaters also lose a lot of energy for reheating. After you use hot water, your heater adds cold water to the heater tank to replace the water you’ve consumed. The gas heater has to heat the incoming cold water, which takes more energy than necessary.
Apart from the problem of energy waste, homeowners without gas lines have to install them on their own when purchasing a gas water heater. Getting a gas line installed requires a series of processes, including obtaining proper permits. So if your home doesn’t have a gas line yet, be ready for some extra costs and a slight delay.
Gas water heaters include storage water heaters and tankless water heaters. These are commonly known as hot water cylinder systems and combi boilers. The hot water cylinder stores already heated water (from a standard boiler) for when it is needed whilst a combination boiler will heat the water on demand. Larger houses with multiple showers and bathrooms may benefit from a cylinder system as it can handle higher water pressure demands.

Electric-powered water heating
An electric water system heats water with electricity from high voltage rods fixed in its tank. Electric water heaters come in different sizes and types. There are whole-house systems, point-of-use heaters, tankless heaters, and storage water heaters.
An electric heater’s size usually determines the amount of energy it consumes. As a rule, large water heaters consume more energy. Although they may be slower, electric water heaters are more efficient than gas water heaters.
As confusing as it may sound, it’s really quite simple. Electric heaters don’t lose any of the heat they generate during the heating process, so they save more energy.
They may be more expensive than gas heaters. Still, electric water heaters are relatively safe, unlike gas heaters that pose safety risks because of the byproducts they emit and possible gas leaks.
Water heater manufacturers usually use energy factors (EF) to measure energy efficiency. Energy-efficient gas heaters typically have an EF of around 0.67, while energy-efficient electric heaters have an EF of 0.95 or higher.
In general, electric water heaters save more energy because they require less energy to operate.
These days, there are energy-efficient gas water heaters, too, for people that insist on using gas water heaters. They are designed to use significantly less energy than usual.

Tankless water heaters
This type of electric hot water system is much more energy-efficient than its tank-based counterpart. Tankless water heaters are highly recommended if you’re trying to save energy and reduce your electricity bill.
They come in both gas and electric designs. If you like the idea of an electric tankless water heater, you can read more about the best brands for single-point and whole-house models, and decide what’s best for you.
Unlike other storage water heaters, tankless water heaters don’t do any pre-heating. They’re also called instantaneous water heaters because they provide hot water only when there’s a need for it. They operate by heating the water through the tap with a gas burner or electric current. With tankless water heaters, there’s no need to store hot water and risk having to reheat the water when it gets cold. Tankless water heaters are the most energy-efficient because they provide just the amount of hot water needed at a time.
Also, against common misbelief, you can use tankless water heaters for large appliances, in the shower, and in the kitchen. Although they may require a substantial cost initially, they last much longer than traditional water heaters. They come in different sizes, and their price varies based on the technology used. Some may be relatively expensive, but you’re likely to find a tankless water heater that suits your preferences and budget needs.
Is it cheaper to use immersion heater or gas 2022?
The year 2022 will be remembered for many years as a time of the energy crisis. However, don’t let this scare you as there are ways to help control your energy consumption and more ways to keep your costs low whilst still keeping warm. Gas or electric heating has its benefits but there are other ways to keep warm and heat your water.
As mention above gas is the cheaper option compared to using an immersion heater, simply because the price of gas is cheaper than electric. There is however a way to help reduce this with a solar panel array and a product called Immersun. Immersun can redirect unused electricity generated by your solar panels to power your immersion heater.
You might have a hot water cylinder installed that is pre-heated with a gas boiler, but has an immersion bypass that not only keeps the water hot, it also has the ability to heat the water without the gas boiler. This is a very handy system as it can work with either gas or electric. Better still, you can link up an Immersun and heat water from your solar panel energy, completely bypassing the gas heating and providing you with free water heating. If the weather is poor and there isn’t enough solar energy to heat an entire cylinder then it automatically switches you back to gas heating.
Gas vs. electric heating – pros and cons
So what are the pros and cons of each energy source? If you have access to a natural gas line and are running a modern gas condensing boiler, then this is going to be the most cost-effective source of heat. We are currently paying 10.425p per/kWh for our gas (Nov 22) and 33.859p per/kWh for our electricity. So gas is 1/3 cheaper than electric.
This doesn’t however mean that a gas boiler is more efficient at heating water. In fact, a gas boiler (even a modern one) is only 80-90% effective due to the loss of heat through the ventilation system. Electric water heaters make use of 100% of the energy and allow you greater control over the temperature of the water output. With the use of smart control devices, you can closely monitor water temperatures and energy loss in an electric water heater. The same level of control can’t be seen in a conventional gas boiler.
For those of you with access to a solar panel system, you may seriously want to consider switching to an electric water heater, especially if you are thinking of replacing an older boiler or water heating system.
Environmentally friendly? We all know natural gas is formed over thousands of years and requires drilling or fracking, then refining before it can be used in our homes. Therefore it doesn’t make for a very environmentally friendly product. For electricity, some are also produced from burning natural elements such as gas, coal and oil but with the increase in renewable electricity, we now have an option. We can choose to buy only 100% renewable electricity from most energy providers but this doesn’t necessarily make this any cheaper. In fact, in many cases, buying 100% renewable electricity doesn’t make the slightest difference. But why not?
This may sound crazy to some. The fact that renewable energy prices are affected by the cost of gas. It doesn’t make sense. Certainly not to me anyway. But the reason our providers keep renewable prices the same as none renewable is due to the way our central electricity grid works. You see, only about 1/3 of electricity is produced from renewable sources. The rest is provided by gas, oil and coal generators as well as nuclear. If the demand for renewable energy outstrips what’s available the grid simply tops up with other sources. An individual energy supplier doesn’t have any control over that. So it’s all a bit of a con. No one supplier can promise the electricity they are providing is 100% renewable! So with this in mind, a supplier cannot reduce their pricing for a specific energy source. It all pretty much stays in line with everything else! Stupid right?
Dependability. This is an important comparison to make when comparing both gas and electric water heating systems. Gas has proven to be a much more reliable system. Even when there is a power cut, most gas boilers will still be able to operate providing heat and hot water when you need it. The same can’t be said about electricity. Storms and other natural disasters can break power lines that travel over the ground whereas all our gas lines are underground and therefore much less likely to be disrupted.
So when comparing a gas vs electric water heater, there are a few key takeaways. Depending on your existing setup, one system might be the cheaper, more energy-saving option. If you are planning a new build and have a say in what energy sources you want then you’ll be able to select the best-performing system for where you live. Off-grid systems are a great option for self-builders and can be scaled to almost any residential size. This also takes away the need to rely on the national grid and heavily rising energy costs. An electric water heater, ground source heat pump or an air source heat pump can be ideal for these situations.
How to save money on your energy bills
Selecting the right heating source is going to be paramount in the future savings of your energy bills. Gas and electricity might be the main sources out there but let’s not forget, there are cheaper ways to heat your home. Firstly I’d like to talk about the alternative heating systems available:
- Log burning stoves and open fires. We don’t need to burn fossil fuels to keep warm. Wood is a natural, renewable source of heat and it can work out cheaper than gas and electric. Installation can start from as little as £1000 and you can even link up your radiators to some stove models. Find free wood or buy from wood fuel companies who are offering the best deals.
Grab 5% discount at Lekto Wood Fuels and White Horse Energy with my discount code – WOODCREATE
- Biomass boilers. Swap your gas, oil or electric boiler for a biomass boiler that runs on bio fuels such as wood pellets, logs and wood chippings. This is a far more eco-friendly approach to heating and can save you money when sourcing the fuels from the right places.
- Air source heat pump. A reasonable up front investment cost but great overall savings on your heating bills. Worth considering if you are staying in your current house long term.
- Ground source heat pump. Similar in functionality to the air source heat pump but draws warmth from the ground. Slightly more expensive to install but again, a great long term saving on heating bills.
- Solar thermal panels or normal solar panels. A solar thermal panel draws heat from the suns energy to heat up your hot water. If you have a hot water cylinder then you can install a system directly onto your normal solar panels that uses the electricity generated to heat your water. Free hot water, what’s better than that!
How to save money with your existing water heating system
Try these top tips to save money on your energy bills without investing in a new primary heating system.
- Turn down your thermostat. Just one degree will make a big difference over time.
- Only heat rooms that you are using. There’s no point in heating the spare room if no one is using it. Simply turn off the radiators in rooms that you’re not using.
- Setup timers and schedules for your heating and hot water heating.
- Invest in a smart system like Hive or Nest to help you monitor and control your heating from anywhere in the world.
- Stop draughts through windows and doors with draught excluder strips. This is a small cost for a big return.
- Wear more warm clothing and snuggle up in blankets and throws to keep warm.
- Unplug energy vampires that drain electricity whilst on standby. TV’s, radios, routers and other similar appliances can use a reasonable amount of energy over the course of a year.
- Keep windows and doors closed during the winter. Use air vents to help circulate clean air in your home.
- Close fridges and freezers quickly as not to release cold air into a room. The same applies to the oven. The longer you have the door open the more energy you lose.
- When cooking on the stove, add lids to your pans as this will help food cook quicker and on a lower heat.
- Make sure your house has suitable insulation, especially in the loft which can be a cheap DIY job.
- If you have a log burning stove, stock up on as much free wood as you possibly can.
Economy 7 to run immersion heater is now 25 p per kWh. Day rate electricity 35 p so although economy 7 has tripled its still lower than day rate. I’ve got a gas fire, but no gas boiler, two storage heaters also economy 7. It’s all very expensive now. I turned off immersion heater in the summer and saved £30 a month, but turned it back on now otherwise there’s no warmth in the airing cupboard. Maybe get a timer installed to run immersion heater for less hours, currently 1 a.m. to 7 a.m. economy 7? But it needs to heat up sufficiently to prevent bacteria in the water?