Trevor S Palmer, Managing Director at Sontay, explains how innovation in wireless sensor technology can save installation time and cost in controls projects.
Government legislation and incentives are driving through changes in building practices and technologies to ensure that the UK meets its 34% emissions cut on 1990 levels by 2020 which is required under the Kyoto Agreement.
Targets for all new buildings to become carbon neutral represent an important stepping stone on this path with legislation in the shape of the Building Regulations driving through these changes. New homes and new schools face a 2016 deadline, public sector non-dwellings are required to become zero carbon by 2018 and other non-dwellings, such as offices, hotels, etc, will need to comply by 2019.
With energy costs rising, it’s clear too that financial pressures are playing a part in greening our building stock. It’s self evident that a more fuel efficient solution will help reduce running costs for building owners and their occupiers in new build and refurbishment projects. Here legislation too is playing its part with the future recasting of the Energy Performance in Buildings Directive likely to extend the burden of requirements on building owners. For example, these will demand that the energy performance of existing buildings of any size which undergo major renovations will need to be upgraded in order to meet minimum requirements. Currently, there is a threshold of 1,000sq m.
Measure & report
At the same time, DECC is encouraging more businesses and organisations to measure and report their carbon emissions as well as set targets to reduce them. The Government believes that improvements here will help contribute to a reduction in fuel usage and carbon emissions.
Soon after coming to power, the Prime Minister announced that in a bid to cut carbon emissions by 10% within 12 months, real time reporting of energy efficiency data would be implemented across 19 ministerial HQ buildings. This information can even be tracked by the public online to ensure that government is, in its own words, improving the energy efficiency of its operations as well as providing transparent evidence on progress. These real time energy meters help departments identify when and where energy is being used and assist them in finding ways to reduce that energy use. The greater adoption of controls technology and the installation of the sensors needed to measure temperature accurately represent an obvious route in helping to achieve many of these objectives.
And yet, in new buildings, project timescales for controls installation can often be extremely pressurised. With traditional wired systems, this can impact adversely upon the ease, efficiency and time and labour costs associated with the controls installation process.
Since existing buildings account for more than 70% of the entire market, retrofit offers a potentially bigger opportunity for energy savings and controls installation than the new build sector. However, here, the cost and complexity of installation can be seen as a barrier to wider adoption. Retrofitting a wired HVAC control system is by necessity a disruptive and expensive business.
And, once the controls have been wired into place, what happens when the internal layout changes because of office churn? Sensors must invariably be moved to accommodate the new requirements. In many cases, the cost and disruption that this process involves means that sensor re-location just does not happen. As a result, the performance of the control system, and efficiency of the building services themselves risk being compromised.
Thanks to new wireless sensor technology it doesn’t have to be this way anymore.
For example, our new SonNet range of wireless temperature and relative humidity sensors are designed to provide accurate measurement of temperature and relative humidity within a building and then communicate these readings reliably to its control system.
Comprising battery powered sensor nodes together with permanently powered network receivers and routers, and software, this innovative product range is built on a robust 2.4 GHz, 802.15.4 self-healing, wireless tree topology.
This topology is significant because it eliminates concerns with reception and reliability often associated with existing ‘point-to-point’ wireless systems.
If a sensor detects a problem with the signal, it will automatically re-route to find the strongest available path to the receiver. Interference with other radio devices in the same frequency spectrum has also been addressed through a proprietary algorithm which continually adapts to site conditions.
By eliminating the need for structural cabling during sensor installation for a HVAC control system, such devices can greatly reduce engineering time and installed project cost. This enables faster and easier installation on new buildings and also opens up the opportunity for control specialists to retrofit energy efficient HVAC controls into existing commercial and public buildings.
Using this type of wireless technology will also bring building owners and facilities managers enhanced site flexibility, allowing for building layouts to be changed on a regular basis without the need to re-wire sensor configurations accordingly.
Such breakthrough wireless sensing technology is already making its mark in the sector. For example, at the Head Office of the Bedford Pilgrims Housing Association (BPHA) in Bedford, it has enabled the speedy retrofit of HVAC controls.
Carried out with minimal disruption to the day to day running of the building, the installation completed by Northampton-based systems integrator AES Control Systems will help improve energy efficiency, reducing carbon emissions for the housing association, and also bring greater building use flexibility for many years to come.
The BPHA administrative base is a four storey office block, dating back to the 1980s, with a prominent glass facade. A controls upgrade was identified as capable of bringing significant improvements to comfort levels for the building’s occupants. In turn, this would minimise fuel consumption of the HVAC services.
“Temperature regulation in our office block, with its large windows all round, had been a huge issue for us” said Matthew Hunt, BPHA’s Facilities Manager. “We needed to improve efficiency but minimise installation cost and disruption.”
AES Control Systems specified Sontay’s SonNet wireless sensor system as the perfect solution for the project.
“We would have faced difficulty in installing cables to sensors across an occupied 4 storey office block, due to the size of the building and the amount of disruption this would present to the office staff in a highly populated, call centre-type environment”, explains Dave Redmond from AES Control Systems. “The wireless option helped us overcome these problems”.
Following a detailed site survey, fully supported by Sontay’s field representative, AES were able to prove that the equipment would work correctly, prior to installation. One SonNet receiver runs a network of sensors alongside one router on each floor of the building. These sensors measure internal temperature and solar gain of the building, helping to regulate the HVAC services for optimum efficiency.
Impact of innovation
The BPHA project is typical of the vast stock of commercial buildings in the UK which, thanks to wireless sensing technology, are now ideally suited to HVAC controls installation. The impact of this particular wireless innovation will help deliver improvements in HVAC energy efficiency and lower fuel consumption in existing commercial and public buildings, alongside
faster, more cost-effective control system installation in new buildings. It is the breakthrough that the building services sector has been waiting for.