Bridging energy harvesting wireless sensor networks to TCP/IP

Changing the status quo
The EnOcean wireless and energy harvesting standard has been on the market for more than 10 years. Now that the technology has matured, an alliance of more than 250 participating companies was formed to push the technology and ensure interoperability between all EnOcean-enabled devices. Several key member companies of the EnOcean Alliance are focused specifically on the development of solutions that bridge existing EnOcean-based sensors and/or switches to TCP/IP networks. Can2Go, Magnum Energy Solutions and BSC-Software are leading the charge in North America to develop controllers/gateways and software that connect sensor data with systems that can make smart decisions about lighting and HVAC energy management in buildings.

Faster installations = faster paybacks
Although wired devices might be less expensive to purchase, the installation of wired solutions, particularly in retrofit scenarios, entail considerably more labor and materials than wireless solutions. In a conventional wired installation, the process involves pulling miles of wire for sensors, switches and controllers. Obstacles, such as asbestos and impassable materials, are frequently encountered when fishing wires through walls and ceilings. Additionally, wired retrofit installations can result in disruption of business operations and building closures. Wired installations often require patching and repainting, which increase the amount of time and labor costs required for the install.

When factoring to the amount of labor and complexity required for the installation of building automation controls, wireless technology has a clear advantage when compared to traditional wired options. Wireless components, such as light switches and occupancy sensors, can be easily mounted on surfaces inaccessible to wired solutions such as glass, concrete or brick. With wired solutions, installers can never be sure what surprises they will find behind buildings walls. With wireless solutions, since no walls need to be disturbed, uncertainty and complexity are significantly reduced.

Dedicated servers and building management software replaced by less costly embedded gateways and web servers
Small and medium sized facilities are seldom equipped with building automation systems because of high upfront costs and long payback periods. The reality is that upfront, fixed costs, including software and dedicated servers, are proportionally more burdensome for smaller installations given their more limited facility budgets. Economic and environmental paybacks are overshadowed by upfront costs.

In the last two years, the development of EnOcean-to-IP gateways and accompanying building management software has made payback incentives more attractive. The EnOcean-enabled gateways and software offer expensive and complex server/software packages. Solutions that traditionally cost thousands of dollars have been replaced by solutions that cost in the hundreds of dollars.

Lighting & HVAC worlds merged into one
Facility lighting and HVAC operations have been handled separately by professionals specializing in two distinct domains. Now, innovative solutions have bridged the historically polarized worlds together. One controller can offer simultaneous wired and wireless control for both lighting and HVAC applications. For example, a self-powered wireless occupancy sensor can provide data that controls both climate and lighting.

The long-standing assumption in the industry was that lighting and HVAC both required their own unique specific hardware, software and integration labor. Because traditional wired controllers have a limited number of physical inputs and outputs (I/O) and because wiring to and from them is affected by building constraints, the industry has kept the focus on application-specific products—leaving HVAC and lighting apart.

The alternative — using single, multi-purpose wireless controllers — significantly reduces the controller and gateway count, which translates into at least halving hardware count. It also dramatically increases scalability, providing buildings with an affordable way to add control points to increase energy savings via building automation in the future.


Ready for the smart grid
The United States Department of Energy has communicated that TCP/IP will be the communications protocol of choice when relaying demand response signals between utilities and buildings. Once a demand response signal is received, the EnOcean wireless protocol is an ideal solution for perpetuating that signal throughout buildings. EnOcean solutions already interoperate with the Smart Grid / Smart Meter world via TCP/IP achieving maximum energy efficiency and cost reductions. With energy harvesting wireless technology as the interface between smart metering and building automation, numerous application scenarios are possible that enhance energy efficiency plus comfort and convenience.