Gas vs Electric vs Tankless – How to choose?
So you’ve decided it’s time to replace your hot water heater. However, between all the options of gas, electric, tankless, condensing, indirect, and more, this decision can start to seem overwhelming. Given that water heating accounts for at least 19% of the energy used in Canadian homes, this decision will have long-term impacts on your utility costs – making the right choice for your home and lifestyle is key. Fret no more dear reader, we’re here to help you ask the questions that will make this decision much simpler.
For one, we should establish that the main divider between types of water heaters is whether they are tank or tankless models. Within each of these two classes of water heaters they are further broken down by their fuel type, either gas or electric. Below we’ll go into the benefits and drawbacks for each style of water heater, ultimately narrowing down the right choice unique to your household and lifestyle.
Here’s a simplified breakdown of some of the differences between gas and electric units of water heaters. Read further to get more detail between tank and tankless systems.
Tankless vs Standard Water Heaters (Table)
| Tankless | Tank | |
|---|---|---|
| Initial Investment | Much higher cost per unit, cost goes up if gas lines and ventilation needs to be installed | Lowest cost water heater, installation costs increase if switching to gas fuel |
| Lifespan | 20-25 years | 10-12 years |
| Utility Cost | Significantly lower long-term (pays for itself by year 6) | Higher long-term costs through energy and efficiency losses, needs replacement every decade |
| Security | No tank to leak or explode | Leaking and explosion risks are present |
| Efficiency | Hyper-efficient | Inefficient |
| Water accessibility | Water never runs out if the unit is connected to power – without power there is no hot water | Finite amount of water is stored and ready for use – hot water can be accessed in power outages |
| Gas (Tank & Tankless) | Electric (Tank & Tankless) | |
|---|---|---|
| Initial Investment | Higher due to ventilation install, higher initial cost of unit | Lower cost per unit, no ventilation required |
| Utility Cost | Lower long-term (saves more money) | Higher long-term (spends more money) |
| Security | Gas lines pose an additional security risk | No gas lines but still subject to pressure |
| Heating ability (FHR) | Heats faster, more efficiently | Can take longer to heat, draws a lot of power |
| ‘Switchability’ | More expensive to switch to gas | Minimal additional costs to switch to electric |
Tank-based water heaters
Tank water heating is the most common type of water heating system that exists today. It is cheap, relatively reliable, and maintenance is simple due to the accessibility of parts and technicians. It also has its fair share of inefficiencies: because of the way it stores and heats water, this style of water heating is considered wasteful in regard to power use compared to its tankless counterpart.
The premise behind this style of water heating is simple: cold water enters a large tank and is heated by a heating element at the base of the unit. When the temperature of the water reaches a preset level (determined and adjusted by you and your water heater technician), the heater briefly turns off. Until hot water is needed at a point-of-demand like a faucet or showerhead, the water heater stores the preheated water in the tank, keeping it to the preset temperature by periodically (or constantly) turning the heating element on and never letting the water get cold.
These units have a general lifespan of 10-12 years due to the way constant exposure to hard water eventually degrades and corrodes internal components. They are also subject to pressure risks and malfunctions that are heightened with limescale build-up. As they get older, tank water heaters require more attention – regular maintenance and servicing of your hot water heater is key, especially with a tank.
The easiest way to choose between a gas or electric tank water heater is to stay with what your previous water heating system used as a fuel source: it is significantly cheaper to stay with an electric-fueled water heater if you had one before simply for the ease of installation – this saves you from the increase in install cost that can come with gas water heaters that need venting and fuel lines.
Gas-fueled tank water heaters
Gas-fueled tank water heaters operate by bringing natural gas and oxygen into the unit, igniting their burners with a pilot light. Because they are combustion-based, gas produces heat faster than an electrical element would, making the refilling of your tank quicker than it would be with an electrical model.
Another way to describe this would be to say that gas-fueled water heaters have a higher first hour rating (FHR), meaning that the rate at which hot water is produced from an empty tank with a gas-fueled unit is higher than it would be with its electrical counterpart. For households with high hot-water demand, gas-powered water heating can be a viable solution for its ability to quickly replenish your hot water supply.
Gas-fueled tank water heaters are more expensive in the initial investment, especially if you didn’t have a gas-powered water heating system before. This is due to the fact that they require ventilation ducts to move exhaust gasses and vapor out of your house. These ducts are often made with anti-corrosion metals and the material cost can be expensive upfront. Furthermore, choosing between direct or power ventilation can add extra costs in labor and parts. This install can easily add $1000+ to your replacement.
There is also an added security risk simply in having an active gas line attached to the unit. While modern units have safeguard valves and pressure sensors, it is still worth noting that gas-fueled units have an extra element of danger: having them installed by a professional and maintained by licensed technicians will allow you to have peace of mind in regard to your water heating system.
Electric-fueled water heaters
While gas units use natural gas to ignite a burner, electric units draw power into a conductive element that is housed in a type of heat exchanger at the base of the unit. Much like a gas unit, electric water heaters will store hot water in their tank and ensure it stays at the preset temperature until hot water is demanded. These units tend to heat water slower than their gas counterparts and as such, tend to have a lower FHR.
Because of this method of heating and storing hot water, electric units draw a lot of electrical power. This is reflected in utility costs when compared to gas models: electric models are more expensive to run in the long-term, no doubt.
Electric units are cheaper on the initial investment however: the cost of the unit itself is significantly lower, given the fact that there are no internal gas lines, gas valves, and gas-related components. Equally, switching to an electrical tank water heater does not need extra labor in terms of installing ventilation and many homeowners are drawn to the electric units to lower their replacement costs.
Despite this lower initial investment, electric water heaters end up being more expensive than their gas counterparts due to utility costs in the long-term. This is a classic case of the “buy once, cry once” mentality: despite being a bit more expensive in the initial investment, gas-powered can save you money in the long term, eclipsing the initial savings offered by an electric unit.
Tankless water heaters
If tank-based is the classic ol’ reliable, then tankless is its future-minded younger sibling. Its tech makes it hyper-efficient and while these units are still a bit inaccessible for those with lower budgets, they’re becoming more affordable every year and the savings they offer are significant.
While tank models heat and store water until it’s needed – resulting in constant energy use – tankless units operate on-demand. That means they are only ‘on’ when a hot water tap or showerhead somewhere in the house is opened. The rest of the time they are on standby, not drawing any energy. This makes tankless water heaters cheaper to run and significantly better for the environment.
It works like this: when you turn on the shower, cold water enters the tankless unit and passes through the heat exchanger. There, it is superheated: mixing valves take this hot water and blend it with cold water, after which it is shipped off to the tap. When the shower turns off, the machine does too. This creates what is – in theory – an infinite supply of hot water. As long as you have power, you have hot water.
Because of the way these units are not exposed to hard water as frequently as tank-based water heaters are, the internal components last far longer. As a result, the lifespan of these units is double that of the tank models on average. This is especially attractive to homeowners hoping to drive down utility and replacement costs in the long-term: tankless units have essentially paid for themselves by the time you would need to be replacing your old tank model. This gives you at least another decade in water heating where you’re actively saving money.
The savings and the energy benefits are thus the main selling points of tankless water heaters. They are better for the environment in the way they are hyper energy-efficient and the utility costs of running them make them far cheaper in the long-run to operate. Furthermore, without the bulky tanks these units are easy to install in most places in the home: point-of-use systems can be placed near appliances on the wall or under sinks, and whole-house units easily fit where the tank once was, with tons of space to spare.
Additionally, one of the biggest perks of going tankless is not the savings but in the security benefits. Tank units are subject to intense amounts of pressure and heat: over time if components degrade too much, TPR valves and corrosion can cause the tank to leak or worse, explode. Tankless water heaters eliminate that risk altogether.
However, these high-tech units are still susceptible to their own drawbacks: because they depend on complicated electrical components like flow sensors, temperature sensors, and control panels to operate, tankless units (both gas and electric) depend on electricity to operate. In the event of a power outage, you would lose access to hot water whereas a traditional tank model would still have a water reserve until power returned.
Furthermore, the initial investment is significantly higher. While it’s becoming cheaper across the board, the average cost of purchasing and installing a top-of-the-line tankless water heater for a 4-person family can run homeowners up to $7000+ dollars, especially if gas lines and ventilation need to be installed.
There are also a few extra considerations that need to be made before installing a tankless unit, like the temperature of the groundwater in your area: if you live in a colder climate, the water entering your home from the municipal source is colder and as a result, the water heater has to work harder to get your water to the desired temperature. This means individuals in colder climates will have to buy higher-capacity tankless units to accommodate for the temperature differential in incoming and outgoing water.
In terms of differences between gas and electric, they are practically the same as the differences for tank models: electric units draw more power but require a smaller initial investment given that gas models need ventilation and gas lines extended into the home. While gas units are more expensive on the initial investment, they are significantly more efficient and cheaper to operate than the electric units: with a lifespan as long as they have, it is significantly more cost-effective to run gas-fueled tankless water heating.
Getting in touch with your trusted hot water heater technician will allow you to fine-tune the decision-making process for your water heater replacement. At Pink Plumbing we work with our clients at every step of the way, ensuring that their new water heater is the perfect match for their budget, lifestyle, and household. Call us today!