Lucy Carew-Reid and Paul Brown
The common cries from staff, in certain council administration buildings, that drive facility managers to distraction are “it’s too hot” or “it’s too cold”! Cries that can even occur in the same place at the same time. And lighting issues (under-lighting and glare) can also be a bane.
Managing large buildings is a complex undertaking, and when a building has a combination of energy efficiency opportunities and thermal and lighting comfort issues, it’s hard to know where to start.
Ironbark recently partnered with HuxConnect and a team of lighting and heating and cooling (HVAC) engineers to untangle Bayside City Council’s administration building thermal and lighting comfort issues, and come up with some solutions that also took advantage of energy efficiency opportunities. The site has been a challenge for many years and with rising energy pricing and ongoing staff complaints, it was time to take action.
Installing Hux’s low cost multi-metric sensors combined with improving how the HVAC system is managed meant actual conditions could be assessed and complaints could easily be separated into those that can be addressed with appropriate apparel (e.g. “wear a jumper”) versus those that require more attention (e.g. changes to infrastructure and management).
Bayside City Council had identified ongoing comfort issues with its heating and cooling system (HVAC) and lighting at its Corporate Centre, and also wanted to make sure the building is as energy efficient as possible.
Given a large component of the project was to analyse staff thermal and lighting comfort issues, Ironbark engaged Hux to undertake an efficiency and comfort review using the HuxConnect system. Close to 100 sensors were deployed throughout the building to monitor temperature and light levels (as well as other variables such as CO2) and staff were surveyed and interviewed about any comfort issues.
Uncomfortable and fluctuating temperatures and light levels were recorded by the sensors in parts of the building, vindicating what staff had been saying and allowing Council to move on from the complaints to focus on solutions.
Figure 1: Hux temperature discomfort floor plan of Bayside Corporate Centre where red = warm/hot, yellow = comfortable, and blue = cool/cold.
Figure 2: A Hux light level example graph (not Bayside City Council) that ranks light levels in an office, showing artificial and natural light components. Few locations in this graph meet the desired 240 – 320 lux at desk locations, with lower levels (160 lux) for meeting rooms and eating areas.
Ironbark’s HVAC and lighting engineers then used this data to assist with two assessments. One was an onsite assessment of the HVAC and lighting hardware that identified a range of infrastructure improvements. The other was an assessment of utility, sub-metering and building management system (BMS) data that found the air conditioning and lighting systems could be managed differently, so they only operated when needed, within appropriate temperature and lighting ranges.
Figure 3: Electricity submeter data revealed that the HVAC system was operating out of office hours on the weekend and during holidays.
The information generated by the Ironbark team has been vital in identifying/validating issues and providing detailed information and evidence to inform the response and enable prioritisation of actions.
Leanne Stray, Sustainability Planning Officer, Bayside City Council
Ironbark’s multidisciplinary team of engineers, sensor technicians and project managers identified and prioritised a myriad of solutions to Bayside City Council to resolve the range of energy and comfort issues – too long a list to profile here.
For ease of implementation, a plan was developed that splits the HVAC and lighting actions into 5 phases spread over 2-3 years.
Lighting solutions were fairly simple – with a range of technology replacements, relocation of fittings and ambient light sensors inappropriate light levels (glare and over and under-lighting) could be addressed.
HVAC solutions were more numerous and complicated. Three that are easy to replicate at other councils are as follows.
Solution 1. Establish a Thermal Comfort Policy and adjust temperature settings accordingly
A Thermal Comfort Policy is a brief and simple document that supports preferred building comfort parameters such as temperature ranges, air quality and ventilation.
Once it is in place, Council has the staff support and management framework in place for making some energy efficiency gains by adjusting the HVAC temperature set point and bandwidth.
The policy can outline:
- That the building needs to meet the comfort levels of staff during hours of operation
- Acceptable and optimal temperature bandwidth and set-points for different seasons.
- How personal space heaters and fans should be used (if at all)
- Guidelines for staff experiencing discomfort within acceptable temperature ranges (e.g. dressing appropriately)
- A formal system for how complaints are dealt with.
This policy is used at several councils in Australia who anecdotally say that a Thermal Comfort Policy:
- Reduces the number of complaints that require changes to HVAC infrastructure and settings
- Provides guidance as to what temperature and bandwidth the HVAC system should be set to
- Lightens the facility manager’s workload and stress levels
- Ensures staff know that their complaints will be listened to and dealt with in a consistent manner
- Puts more onus on senior management to do something about an inadequate HVAC system
An essential component of this policy is ensuring you gain buy-in of key staff including facilities management and safety representatives.
Solution 2. Set up the BMS so the building is only air conditioned during occupied times
Most BMS’s can have an automatic “Optimum Start Function” installed that will prompt the HVAC system to turn on automatically when it needs to in order to reach optimum conditions by occupied times based on ambient temperature levels. All council has to do is program occupied times into the BMS system.
It’s not rocket science, it’s inexpensive, and in the case of Bayside City Council is due to save around $15,000 in annual energy costs.
Solution 3. Set up a regular HVAC BMS management optimisation process
Regularly review your BMS data and fine-tune the HVAC system accordingly to ensure that system settings remain optimal and opportunities for ongoing improvement are identified.
Reviews can be high level or low level and should take place at least twice a year at the beginning of the cooler and warmer seasons and also after any changes are made to the HVAC system.
Prior to the review, make sure your council has some quantifiable performance metrics to ensure that all stakeholders are clear on HVAC expectations. Targets should relate to energy consumption and any standards around temperature and time settings developed via a Thermal Comfort Policy.
The more regular the review, the less chance there is of ‘drift’ taking place in optimised set-points, and the more chance there is of improving staff comfort.
To ensure a comprehensive assessment can be achieved (either by staff or consultants), set up the BMS system so all relevant data is visible at the front end of the BMS and that BMS data can be easily accessed by external parties.
See here for a separate Building Optimisation Article - Pearls of Wisdom from Local Government Operatives
There are a few simple lessons for all councils from the Bayside experience. These are summarised below:
- Sustainability for simple buildings can be delivered using a simple audit + Action approach periodically
- For complex buildings, typically your top 5-10 energy consumers, or any sites where ongoing complaints cannot be resolved easily, a more comprehensive assessment, planning, project delivery and ongoing systems monitoring and optimisation program makes sense
- The use of policies to support staff to enforce conditions is critical
- Using external or internal providers who understand how local governments work and who can assist in reaching agreement on the problem and the approach to deal with this is critical and drives an effective outcome
If you would like to discuss the project in more detail or understand the learnings more please contact Lucy Carew-Reid or Paul Brown on 1300 288 262 or email@example.com, firstname.lastname@example.org. Or check out more great stuff from our friends at Hux!