The idea of ​​devices working on their own, without plugs or disposable batteries, sounded like science fiction a few years ago. Today, thanks to the combination of connected home, solar energy, biotechnology and smart managementIt's much closer to becoming commonplace. From locks or sensors powered by a simple flick of the wrist, to textile patches that generate electricity from sweat, the landscape is changing at breakneck speed.
In this context appear the smart devices that generate their own energyA family of solutions that not only save on cables and batteries, but also make better use of the energy we already have available: sunlight, heat, movement, or even the chemical compounds in our bodies. Let's take a look, calmly and with very specific examples, at how all this works and what impact it can have on the home, health, sports, and everyday life.
Energy harvesting at home: devices that are self-powered by movement
Engineers and research centers have long fantasized about extracting energy from virtually anythingThe sound of shoes brushing against the ground as you walk, cars passing by on the road, or even the vibrations of a bridge. For years, it remained more in the laboratory than in the living room, but recent technology fairs like CES in Las Vegas have shown a clear shift: these ideas are beginning to take shape as real products designed for the connected home.
One of the companies that has made the most noise is Gemns, specializing in what is known as energy harvesting applied to home automationTheir proposal is based on small modules capable of generating a brief but sufficient electrical pulse from an everyday gesture, as do the triboelectric sensorsTurning a knob, pressing a switch, or moving a handle. That pulse won't power a refrigerator, of course, but it will send a robust wireless signal to other devices in the house.
The heart of their system is a device similar in size to a large coin. Inside, a The magnet spins rapidly in a microgenerator When the user performs a mechanical action (for example, opening a door), this movement induces an electrical current that is stored in a capacitor and, almost instantaneously, discharged to power a small radio frequency module. The energy generated lasts only a moment, but it is more than enough for the smart lock to receive the command or for a sensor to alert that the door has been opened.
More advanced models, such as the Gemns G200, use these pulses for more than just a simple "on/off" function. In a smart dimmer switch, for example, The gesture of pressing or turning can be translated into commands to dim the light.This allows you to turn on a lamp located elsewhere in the room or activate pre-configured scenes, all without a continuous power supply or batteries to replace. Technically, we're talking about tens of milliwatts generated instantly: a short time, but more than enough power for the low-energy radios used in Zigbee, Thread, or other home automation protocols.
The main practical consequence of this approach is that Wiring and battery maintenance are avoided. throughout the home. Installing door/window sensors, wireless switches, or wall controls no longer requires construction work or worrying about running out of batteries. Furthermore, as they are self-contained modules, they can be easily relocated if the layout of the house changes.
Wireless charging and ambient light: alternatives without plugs or batteries
Motion is not the only energy source available for these smart devices. Other companies are exploring Wireless power methods based on energy fields, light, or small solar panelsdesigned primarily for low-power locks, sensors, and cameras that do not require a high continuous current.
One striking example is Willo, which works on truly wireless charging solutions: instead of placing the device on an induction base, a energy field capable of powering devices located within a certain radiuswithout the need for physical contact. The idea is that, in the same space, several sensors or actuators can receive the necessary energy without depending on cables.
Another different proposal is AuraCharge, from the company Lockin. In this case, the transmission is based on a directed beam of light that carries energy up to a few meters awayProvided there is a clear line of sight. This is especially useful for smart locks on interior or exterior doors, where installing a large solar panel wouldn't make sense, but a well-oriented light emitter could be placed.
In addition to all this, manufacturers add small miniaturized solar panels in sensors and other gadgets These panels don't always completely replace the battery, but they allow it to be kept charged by harnessing ambient light, whether natural or artificial. This way, autonomy is extended for months or years, and the user hardly has to worry about anything.
It's worth noting that, in most of these cases, the main objective isn't so much massive energy savings as comfort and reduced maintenance. The safety sensor can consume less than 0,5WMany locks can run for months on a simple set of alkaline batteries. What changes with these technologies is that they minimize the need to travel to inconvenient locations to change batteries and, incidentally, reduce the amount of waste generated.
According to companies like Gemns, the real cost lies in Place devices in complex locations and check them frequentlyIf that task disappears because the very act of opening a door or turning on the living room light keeps everything running, the system becomes more scalable and sustainable, especially when we're talking about hundreds or thousands of sensors in a building or critical infrastructure.
Where these self-powered devices shine (and where they don't)
Energy harvesting technologies, energy fields, or mini solar panels fit particularly well in devices that don't need to be always activeInstead, they operate based on "events" or specific actions. A lock that only requires a single press to open, an opening sensor that sends a signal when it detects movement, or a switch that sends a radio command every time you press it, are perfect candidates.
However, for devices such as video surveillance cameras, voice assistants, routers, or home automation hubs, which require continuous power supply and significantly higher power outputThese solutions are not yet viable as a primary energy source. Power outlets and, at best, high-capacity batteries connected to conventional solar panels still reign supreme.
The design of self-powered devices usually revolves around the same principle: to capture transient energy, store it briefly, and release it in a controlled mannerThis is achieved using high-capacity capacitors or small storage systems that charge with each movement or with the radiation received. Then, an ultra-low-power electronic circuit decides how and when to use this small energy "reservoir."
Integrated into a smart home ecosystem, these devices offer enormous potential. It is estimated that millions of home sensors could be installed without the need for regular maintenance, reducing the volume of discarded batteries and making it easier for homes and buildings to integrate smart home technology. dense networks of measurement and control pointsFurthermore, being compatible with low-energy protocols such as Zigbee or Thread, they can coexist with other devices on the market without creating closed technological "islands".
In short, it's about choosing your battles wisely: Not every gadget can do without a battery.However, there is a very wide range of uses where it is possible and, moreover, makes a lot of economic and environmental sense.
Smart plugs: make the most of the energy you already generate at home
Beyond generating miniature energy, a key part of the domestic revolution involves manage the electricity we already produce or buy wiselyThis is where smart plugs come in, small adapters that connect to any power outlet and allow you to automate a regular household appliance on the fly.
A smart plug is placed between the wall and the device you want to control, and acts as a switch controllable via Wi-Fi, Zigbee, or similar protocols. Thanks to an app, a voice assistant, or a centralized home automation system, you can... turn the equipment on or off, schedule times, view consumption, and integrate it into automations more complex. Suddenly, an old washing machine or an electric water heater without connectivity becomes part of your smart home.
In the field of photovoltaic self-consumption, these devices are invaluable. The biggest problem with solar panels at home is that They produce more energy at midday, precisely when there is often no one at home.This surplus is fed into the grid and compensated on the bill, but economically it is usually more profitable to consume your own production directly than to "sell" it to the system.
The beauty of smart plugs is that they allow synchronize the use of appliances with the solar generation curveFor example, you can program the dishwasher to start when the system exceeds a certain power level, the water heater to activate only if there is excess heat, or the dryer to run during peak sunlight hours. This can be done on a fixed schedule or, even better, by connecting the plug to a monitoring system for the photovoltaic installation.
The basic setup is usually simple: you plug in the device, connect it to Wi-Fi and the control system, and from there you can Control it from your mobile phone, receive consumption alerts, and integrate it with Alexa or Google Home. and even export data. Some advanced models allow rules such as "if solar production exceeds X watts for Y minutes, turn on this device." In other words, they react in real time to the behavior of your own installation.
Their true potential is unlocked when you combine them with energy monitoring platforms (such as those from major inverter manufacturers or installer apps). These tools show real-time production, consumption and grid feedallowing you to adjust the activation points of each smart plug: the water heater only turns on if there is a clear surplus, the laptop charger only during the cheapest or sunniest hours, etc.
Practical applications in self-consumption, batteries and air conditioning
Smart plugs have very specific applications in a home with solar panels, and some are particularly interesting due to their potential economic impact. One of the most obvious is automate high-consumption appliances such as washing machine, dishwasher, dryer or oven, so that they operate during peak generation hours, even if you are not at home.
Another very profitable use is the control of electric water heaters and boilersHeating water requires a lot of energy, and if you do it when your solar system is producing more than needed, the savings are significant. A smart plug can turn on the water heater when it detects excess energy and turn it off when the desired temperature is reached or when production drops, making the most of every kWh coming from the roof.
It is also useful in charging small devices and toolsCordless vacuum cleaners, computers, drills, scooters, or garden batteries. Instead of leaving chargers plugged in all day, you can program them to only work during daylight hours, minimizing phantom loads and, incidentally, improving battery life by preventing constant overcharging.
If you have domestic batteries for storing energySmart plugs help define priorities. You can program certain appliances to operate only when there is direct production, allowing others to be powered when the battery is full or when off-peak electricity rates are cheaper. This way, you get the most out of both your solar panels and storage, minimizing electricity purchased from the grid during peak times.
Even in air source heat pumps or heating and cooling systems, where time-based control is essential, these devices can make all the difference. A smart plug or a connected relay can activate the heat pump during periods of high solar productionThis involves pre-heating or pre-cooling the home to avoid drawing excessive power from the grid during peak hours. The same principle applies to simpler electric vehicle chargers, where an intermediate smart plug limits charging to specific times or periods of abundant sunlight.
In terms of benefits, the use of these plugs in homes with self-consumption translates into More direct self-consumption, less dependence on the grid, better use of batteries and a lower electricity billTheir price is usually affordable, so the usual recommendation is to start with one or two high-consumption appliances and, depending on the result, expand the number of monitored points.
Wearables that extract energy from sweat: the SELF-SENS project
The idea of ​​smart devices that generate their own energy isn't limited to the home. A new generation of devices is emerging in the health and sports sectors. Wearable sensors that are powered by our own bodyA good example is the SELF-SENS project, coordinated by the Energy Technology Institute (ITE) together with the textile research center AITEX.
SELF-SENS is committed to creating Smart textile patches capable of monitoring health and performance parameters in real timeThese patches measure electrophysiological signals or lactate concentration while the person goes about their normal life. The key is that these patches obtain the sample directly from sweat or interstitial fluid under the skin, without the need for uncomfortable punctures or traditional conductive gels.
To power all the necessary electronics, the project is developing enzymatic biofuels that They generate electricity from compounds present in sweatIn other words, the body itself becomes the energy source. The project will focus on several prototypes: a biobattery integrated into a textile patch that converts sweat into energy, a wearable sensor that records signals such as ECG using dry electrodes, and a biosensor that measures lactate in interstitial fluid.
The lactate parameter is especially interesting in sports because It indicates the level of effort, the state of recovery, and the risk of injury.To access the interstitial fluid, micro-extraction systems are used to channel the fluid to sensors integrated into the patch. The entire system is designed to be comfortable, discreet, reusable, and made with biocompatible and washable textile materials.
The electronics integrated into these patches must be ultra-low power consumption, precisely so that the energy obtained from the biopile is sufficient. The combination of automatic sample collection and energy self-feeding This means the user doesn't have to worry about recharging the device or changing batteries, which facilitates continuous monitoring on a daily basis.
The project has the collaboration of several companies from the Valencian Community, which will help define requirements and validate prototypes in real-world environments, especially sports settings. Its expected impact is twofold: on the one hand, a better prevention and health monitoring, especially in people with chronic illnesses or older active individuals; on the other hand, a reduction in the use of conventional batteries and electronic waste, moving towards solutions more aligned with the circular economy.
Smart homes that generate and manage their own energy
If we add all of the above to the boom in photovoltaic installations, the result is the idea of ​​a smart home capable of producing a good part of the energy it needs And, moreover, to manage it automatically to make the most of it. It's no longer just about putting solar panels on the roof, but about integrating them with home automation, smart plugs, climate control systems, and battery storage.
A connected home can detect how much solar radiation it's receiving, the production level of the panels, and its current energy consumption. From there, tasks such as charge devices and appliances during times of surplusAdjust thermostats, move blinds to reduce air conditioning use, or prioritize charging electric vehicles when energy is more abundant or cheaper.
In many cases, installing home automation without solar power allows for some savings, but you still depend on grid electricity rates. The real difference comes when The house generates its own electricity and automation decides when and how to use itWith good solar panels, it's possible to cut your bill by up to around 80%, and if you add a properly sized battery, there are scenarios where energy costs approach almost zero at certain times of the year.
Among the benefits of this combination, the following stand out: significant bill reduction, greater convenience by being able to control everything from your mobile phone or by voice, a smaller carbon footprint and greater resilienceIn the event of a power outage, a battery-powered facility with critical systems powered by renewables can continue to operate, maintaining basic lighting, communications, and security.
The path to achieving that self-sufficient home is usually taken in stages: first the photovoltaic installation, then the incorporation of smart devices (light bulbs, plugs, thermostats, blinds), then the battery to store surpluses, and finally advanced automation through energy management systems that learn from your habits and adjust consumption almost invisibly.
Photovoltaic systems and advanced management in the smart home
For a home to truly benefit from its solar panels, it's necessary to understand how a solar panel is composed. residential photovoltaic system and how it integrates with the rest of the homeBeyond the panels on the roof, there are a number of key components that allow sunlight to be converted into usable energy and managed intelligently.
Solar panels are made up of photovoltaic cells, usually silicon, which They convert light into direct current (DC)Their number, type, and arrangement determine the peak power of the installation. They are mounted on fixed structures or solar trackers that optimize their orientation. All that energy travels through the wiring to the inverter, the true brain of the system.
The inverter transforms direct current (DC) into alternating current (AC), which is what outlets and most household appliances use. It also typically handles... synchronize with the grid, manage electrical safety, and provide accurate production dataAlong with the cabling, the protection elements and, where present, the storage system (batteries or ESS), they complete the physical part of the system.
Almost all modern systems incorporate monitoring platforms Accessible via web or app, you can view the generation curve, household consumption, and, in some cases, the energy exported to the grid. More comprehensive solutions, such as smart home hubs, go a step further: they also collect information from other devices (plugs, thermostats, car chargers) and allow you to create automations based on that data.
When you integrate solar production with an advanced home automation system, it is possible to achieve intelligent load balancingIf a surplus is detected and electricity prices are high, washing machines, heat pumps, or vehicle chargers can be activated. Conversely, if the house is importing too much energy from the grid, power consumption can be reduced or non-essential loads switched off to avoid exceeding certain limits or entering expensive tariff tiers.
You can also use dynamic pricing and price forecasting. For example, if a significant price increase is expected in the afternoon and the morning is sunny, the system can decide activate dishwasher, preheat domestic hot water or charge battery to reach those times with the maximum possible stored energy. Similarly, if the grid is very cheap during a period of low solar generation, it may be more cost-effective to store the surplus for another time.
Batteries take on a special importance in this scenario. An energy manager can decide when to charge and discharge based on the excess or deficit of solar energy and the cost of grid electricity, maximizing independence. In this way, the home is not only able to produce electricity, but also to use it strategically, avoiding import peaks and making the most of every kWh.
Finally, by combining solar production data with smart climate control, the system can to heat or cool the home in advanceThis includes harnessing solar radiation at specific times to accumulate heat for domestic hot water or activating ventilation when energy costs are lower. Ultimately, it's another step towards self-managing homes that optimize comfort and energy consumption.
Solar-powered appliances and other solutions that run on the sun
It's not all about large rooftop panel installations. There are increasingly more household appliances and devices that run directly on solar energydesigned for people who do not want (or cannot) make a large initial investment, but do want to reduce their dependence on the grid and their environmental impact.
One of the most widespread products are the portable solar chargers for mobile phones, tablets or other gadgetsThey incorporate small, foldable panels that capture sunlight and transform it into electricity available through USB ports. The more panels they have, the greater their charging power and the less time it takes to charge your devices. They are very useful on hikes, trips, or in situations where there are no electrical outlets nearby.
There are also systems of security cameras powered by integrated solar panelsSince they are usually installed outdoors, they can take advantage of direct sunlight to keep an internal battery charged during the day and operate at night. This greatly reduces the need for wiring and facilitates installation in locations far from power outlets, such as driveways, gardens, or building facades.
Another classic are the solar water heatersThese systems replace or supplement conventional boilers and electric water heaters. They consist of an outdoor solar thermal collector and a storage tank where the hot water is kept. They are particularly advantageous for homes with good sun exposure, apartment buildings, and indoor swimming pools, where they can offer significant long-term savings.
As for the kitchen, in addition to using the energy generated by photovoltaic panels to power the hob, oven or microwave, there are solar cookers that concentrate the sun's rays using reflective surfacesAlthough they may be bulky, they reach temperatures above 300°C, enough to prepare practically any dish without consuming electricity or gas.
Finally, it is worth mentioning the systems of air conditioners powered by solar energyThey are usually somewhat more expensive than conventional units, but they allow you to reduce mains energy consumption by between 35% and 50%, while maintaining similar cooling capacity. They can pay for themselves in just a few years, especially in warm climates where air conditioning costs are very high.
All these solutions, from the small portable charger to the solar air conditioner, share the same approach: to directly harness the energy available in the environmentreducing electricity bills and associated emissions, without the need for large infrastructures or complex works.
The common denominator of all these advances is that our homes, personal devices, and even our physical activity are beginning to transform into intelligent energy sources and managers. By combining solar panels, smart plugs, energy harvesting systems, textile biofuels, and a healthy dose of automation, it's possible to build much more efficient, comfortable, and sustainable environments, where every gesture, every ray of sunshine, and every drop of sweat counts when it comes to powering the technology that surrounds us.
