Unleash the power

New technologies have emerged that can power up security systems without wires or batteries. Solar, wireless power transmission and energy harvesting solutions are environmentally friendly alternatives that can also reduce maintenance and installation costs.

Advanced security systems rely on some kind of power. A typical access control system might include several electrical devices – such as magnetic locks, an automated door closer, a smartcard reader and a security camera, which may also need to network with a central monitoring system. Wiring all these devices can be problematic, as Dave Gray, General Manager at Norton Door Controls notes. “There’s an upfront expense in new construction, and with retrofits – if you don’t have the power access and the right kind of power, it can be very disruptive and very expensive to address.”  

batteryBatteries of course eliminate the need for electrical connections, but cause other issues. For security systems, reliability is paramount: For example, if a door with magnetic locks loses power, it will default to an unlocked position and batteries must be regularly checked and replaced, increasing maintenance costs and generating waste.  

They are also expensive: According to David Schatz, director of marketing at WiTricity Corp., generating a kilowatt-hour of electricity with AA batteries costs approximately $350 – as compared to closer to 10 cents for household power lines. It’s no wonder that vendors have been seeking another way.  

Here comes the sun
New technologies, such as solar, wireless power transmission and energy harvesting solutions, can provide power without wires or batteries and are making it possible for companies to reduce installation and maintenance costs as well as impact on the environment.  

Solar power doesn’t require any type of connection to the power grid, but the need for bright, consistent light means solar is rarely suitable for interior locations. In typical consumer or business settings, solar has mostly been used for applications where absolute reliability is not required. For example, solar-powered security cameras won’t leave buildings open to intruders if they fail.  

Some solar-powered systems have emerged for specialized applications where they can benefit from unlimited sun. MAPSANDS was developed by US Global Nanospace for border protection in remote desert locations such as oilfields – where sun is plentiful but powerline connections or regular maintenance visits are basically impossible. MAPSANDS includes large solar-powered security stations that can detect an intruder and then issue auditory warnings and alarms, or even deliver an armed response.  

Through the airwaves
Of course, a system like MAPSANDS is literally overkill for most power control needs. In the average building power is usually somewhere nearby – and WiTricity can help fill the gap. Developed by a team of researchers at MIT, it converts electrical power to a magnetic field which can then be wirelessly transferred – through brick or walls if needed – to devices equipped with a capture device and converter. For relatively low-power needs like access control, devices can be as far away as a few meters from the power source, which can be simply plugged into an outlet or embedded in a wall, as desired.  

As noted by Dave Schatz, WiTricity’s key advantage is “a steady and predictable stream of power.” While the idea of wireless electricity may give one pause, since the power is converted into magnetic fields – and WiTricity also complies with existing health and safety standards regarding magnetic exposure – it’s completely safe, and won’t cause interference with other wireless devices like cellphones. The main limitation is an inability to transmit through metal – so while power can be sent around steel beams, it won’t work through metal walls such as those found in armored bank vaults. WiTricity is an emerging technology and has not been integrated into security solutions yet; however, the company is working actively with OEM partners in a variety of areas, so stay tuned for future developments.  

Self-powered technologies are another possible solution – using the energy created when a knob is turned or a door is opened. Initial products required some compromises; for example, requiring a user to pump a door handle three or four times to “charge” a system prior to gaining access.  

The new Trinity door closer from Norton addresses this issue with an extremely efficient energy harvesting system that is transparent to users. “Any movement of the door of 10% or more is enough to generate power,” notes Norton’s Dave Gray. Therefore, even if the door is untouched for months and powers down fully, a single attempt to open the door would immediately bring it live. With no need for external power and intelligent self-adjusting technology, the Trinity system is gaining attention from beta customers seeking a green solution as well as one that requires almost no routine maintenance checks.  

According to Gray, the same self-powered approach could potentially be used for networked access control systems as well – for example, systems that use WiFi to communicate door status. This opens the way to a future in which access control devices can be a fully integrated part of a security network without connecting to any wires at all. With the strong potential savings that could be achieved by eliminating the need to break into walls or swap out batteries, organizations of all types are likely to embrace this new opportunity to cut the cord once and for all, and bring intelligent access wherever it’s needed regardless of existing infrastructure issues.


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