The rise of smart shower heads: overcoming the technological and power limitations

Updated: Jul 27

Taking a look at the different types of smart shower heads, smart shower system on how they are evolved with the advancing power supplies, out of the shower head and inside them.

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Shower heads are dumb for too long

Showers or shower heads have not been generally associated with the word smart until recently. That’s pretty remarkable given that the first ever shower head was demonstrated way back in 1767 in London. That’s earlier than the first modern automobile, elevators or even the first use of lightbulbs.

People’s lives have drastically changed since the 18th century. About 100 years later electric pumps were invented and people could open the tap and have pressured water, modern toilets, sinks faucets, steward systems were implemented, showering and bathing became a lot easier.

Fast forward to the 1950s, showering took over taking baths and it became the standard option for everyone for everyday washing and self-care. The amount of shower heads sold suddenly sky-rocketed, however the shower head pretty much stayed in its original form, a simple sprinkling device, despite other kitchen or bath utilities having all had significant upgrades over the years. We have automatic dishwashers, laundry machines, and all other upgrades of products with the addition of power.

In the 1980s, when the phrase “smart home” first became a buzzword, more and more home automation products were introduced. Things like motion sensing lights, automatic garage door openers, programmable air-conditioning thermostats, home security systems and wireless telephones were all revolutionary in those days.

After the first smart home wave, the second smart home wave revolutionized home utilities along with the concept of the “Internet of Things''. This was the introduction of smart doorbells, smart locks, smart refrigerators, vacuum robots, home cameras that connected to phones, smart speakers that controlled your light or shades with a snap of a finger. All home appliances and furniture have received a full round of upgrades in the past decades. Shower heads have been improving as well, with additional spray modes, limited flow rates, and different colored showers every year.

The missing piece of smart showers — electricity

Perhaps the biggest reason that shower heads or shower devices are not able to have more functionality and enjoy some of these modern benefits of electronics is because of the limitation of power. It is not a surprise, after all, having electricity and water in close contact is a safety hazard. Almost no one puts power outlets into the shower stall or bathtubs where water splashes around easily. However, over the years, we do see glimpses of the development of a smarter, better, function rich shower head. We will summarize this for you in the article as we look into the future of smarter bathrooms.

Here are some common sources of power for shower heads or shower systems today:

Plug-in power



Hydro-generation in shower head

Heated shower head, electric shower, power shower

photo credit: By User:Chixoy - Own work, CC BY-SA 3.0,

There are some shower heads that you can plug-in that heats up water instantly. The so-called power showers, electric showers, or the “suicide showers” show up in places where heating water tanks wasn’t popular or difficult to implement, quite common in older buildings in southern America. These showers have heating filaments embedded inside the showerhead, often a big resistor or inductors for heat generation. As water flows through these heated metal pieces, water is heated instantly for shower use. Whether it’s having a plug-in outlet next to the shower head, or routing electricity from far away to the shower head, it is a safety hazard to heat water instantly and It certainly has caused casualties over the years.

A slightly more advanced design comes from a company called Marey where the shower head is more considerately constructed with all wires and other vulnerable parts are well sealed and requires installation by experts. This is an example of how instant heating can work safely and without concern for water splashing causing injury to the shower user.

Another common shortcoming for this type of electric shower is that the flow rate is limited. Water has a pretty high heat capacity, meaning that it takes quite some energy to heat up the water compared to heating up an aluminum pan. The specific heat of water is 4190 J/kg*°C, that means it takes 4190 Joules to heat 1kg of water by 1°C.

Assuming water commonly settles at 25°C, to increase the temperature to 40°C which is equal to 100 °F, the common shower temperature, the energy used is 104750 Joules per 1kg. National shower head flow rate is 2.5 gallons per minute, which is 9.5 liters of water per minute. To have water instantly for a 2.5 gallons shower requires 995125 Joules, that’s a whopping amount of energy required. That’s why tankless heating often has a 30,000W rating (compared to 1,000 for a washing machine). So these tiny instant heaters would need to limit the water flow to avoid drawing too much current otherwise the power consumption would be safety-exceedingly high if a high flow instant heating showe head existed. That’s why even for Marey, the flow rate is limited at 1.5 gpm for this type of heated shower.

Smart shower systems

photo credit: Hansgrohe RainPad

Since it is dangerous to use a plug-in a shower head, why don’t we hide them and protect them behind the wall when modeling the house? This is something that could be designed within the structures of a building or plumbed in before a bathroom remodel.

Without a power problem, kitchen and bathroom suppliers are more than capable of creating function-rich products, as the sensor technology to expand upon these kinds of smarter functions are readily available. For example, the touchless sensor faucets we commonly see in airports or hotel lobbies were created more than 30 years ago. We can see more examples of complex and advanced technologies within our everyday appliances such as modern washing machines and dishwashers, so why wouldn’t this translate to other appliances in our home. Voice activations, LED screens, remotely turn on water, electric thermostatic valves for shower temperature controls, all of these features can be found in your smart phone or common appliances wouldn’t be hard if permanent access to electricity was possible. A full digital experience of shower system. One way to implement this is when new buildings are built, or when remodeling, these items should be installed into the walls by professionals to make sure that there’s no safety issues.

One of the downsides of this approach is that it’s expensive and difficult to apply, which causes a lower volume for production resulting in higher cost, and it is also expensive to implement costing even less people willing to buy hence even lower demand. That is why these shower systems usually cost more than a thousand dollars and can add significant expense to install such a system with the added necessity of a plumber.

It seems that every major brand has a smart shower system offering, like Kohler, Moen, yet the adoption rate is not very high. Would you spend more than five thousand dollars on a voice activated smart shower system?

So what else can we do without the need of plug-in or remodel?