Making the Smart Home More Sustainable

Smart home devices skyrocketed in popularity throughout the pandemic. These smart devices can make you more productive, provide entertainment, and keep you safe. It’s also exciting to think about how IoT can make your home greener.

Sustainability in the Smart Home

Last year, global electricity demands rose 6 percent, straining local supply chains and pushing up electricity prices. These rising energy demands are quickening the pace of global warming and contributing to the climate crisis. There are many ways to help stop climate change, including switching from fossil fuels to renewable energy and protecting rainforests like the Amazon. But what can we do at an individual level to help?

One thing that we can all do is use less electricity. Don’t worry, that doesn’t mean you need to sit in the dark. Rather, it’s important to try and minimize energy waste. Reducing our energy usage en masse can make a huge difference, and smart devices are designed to help lower our household energy usage.  

Smart thermostats make it easy for users to set their preferences and adjust the temperature and AC from their smartphones – whether they are on their couch or on the go. With advancements in AI, smart thermostats are now learning how to better anticipate users’ heating and cooling preferences based on usage patterns. These smart systems can help significantly reduce your energy usage and energy bills, a win-win for consumers. Plus, smart thermostats can help you detect when there is a problem with heating or cooling systems and provide reminders about when it’s time to change air filters.

Smart lighting is another amenity that helps with sustainability. Smart lighting systems allow you to set your lighting preferences based on location, the time of day, and whenever the system detects that someone is home. This type of customization, along with using efficient LED bulbs, can go a long way in reducing energy usage.

The Need for Energy Harvesting

To become more sustainable, the IoT industry needs to address its battery problem. Every year, billions of batteries are thrown out, leaking harmful chemicals into landfills. Energy harvesting offers a solution.

Smart devices can use energy harvesting technology, combined with other low-power enhancements like Lowest Power Radio and On-demand Wake Up technology, to extend battery life so a single battery can last the lifetime of the smart product. In some cases, energy harvesting technology can even allow devices to operate without any batteries at all. In addition to the convenience factor of not having to change batteries, users benefit from the cost savings. At scale, smart devices with energy harvesting will help the IoT industry become much more sustainable.

Energy Harvesting Sources

There are a variety of energy harvesting approaches that smart devices are leveraging today, including photovoltaic (PV), radio frequency (RF), mechanical motion, and thermal. PV is one of the most popular approaches for energy harvesting in the IoT industry, especially for human interface devices such keyboards and mice. One thing that might surprise a lot of people is that modern PV cells don’t require much light to harvest energy. PV cells can easily harvest light at typical indoor light levels and can even harvest energy from non-visible light sources such as infrared. Today, glass substrate is the most common material for PV cells, but continual innovations in PV technology are enabling PV cells to be built with more flexible materials. These new materials will make it easier to integrate energy harvesting into more IoT devices with more elaborate physical shapes and sizes such as environmental sensors and beacons.

RF energy is an option that uses an RF source (i.e. a transmitter) to power devices nearby. The frequency, transmit power, and duty cycle of the transmitter all factor into how far away devices need to be from the transmitter. Power can be transferred using any frequency, but devices can be up to five or six meters away from the source when lower RF frequencies (such as 900 MHz) are used. RF offers a great way to power multiple devices at once, making it a great solution for retail or industrial environments including factories.

Mechanical motion provides another option for energy harvesting technology and can come from a variety of sources, such as the actuating motion of a button press or the vibration of a motor. The pressure on the sole of a running shoe can also be used as a mechanical source for energy harvesting. Some examples of mechanical harvesters include resonant vibrational harvesters for motors and piezoelectric generators that respond to mechanical pressure.

Finally, thermal energy is another readily available energy source to power wireless monitors and sensors. These heat sources could include motors, hot water pipes, and even the human body. IoT devices that rely on thermal energy use a thermoelectric generator (TEG) that converts the temperature gradient between a heat source and the ambient environment into electrical energy.

While there is still a lot of work that needs to be done to mitigate the effects of climate change, smart devices, when accompanied by energy harvesting technology, can now be an essential part of our sustainability efforts.