Conservation and demand management (CDM) specialists frequently use the term “low-hanging fruit” in reference to low-cost or no-cost sources of energy savings. Michael Lithgow, P.Eng., LEED AP BD+C, offers insight, drawing on his experience in private multi-residential management/operations and his current role as manager of corporate energy services and municipal energy conservation officer for the Regional Municipality of York.
Where are the greatest and easiest energy savings still to be found?
I’m excited about a couple of initiatives: one which is likely fairly obvious to property and facilities managers; and the other which may, at first glance, seem more futuristic.
- LED lighting has evolved so quickly in the last couple years that it has supplanted all other light sources – halogen, compact fluorescent, T5 fluorescent, HPS, metal halide – in York Region’s construction standards. Linear T8 fluorescents are the only remaining old technology and even T8s will be gone very soon. Energy reduction is 40 to 90 per cent depending on the application. Light quality and controllability is exceptional, and lifespan looks to be impressive. So we’re doing a lot of indoor and outdoor retrofits, even in the most challenging applications.
- Like LED lighting, electric vehicles or EVs are a game-changer, though it may not be so obvious yet. Facilities represent just one-third of the energy use in Regional operations, the rest is vehicle fuel. EVs finally offer a viable option for achieving drastic reductions in vehicle energy cost and greenhouse gases (GHGs). There’s even the potential for a symbiotic relationship between vehicles and buildings to develop, with evolving grid-interactive vehicle battery technology.
Where have the greatest and easiest savings already been found?
Lighting and water retrofits have been the greatest and easiest savings in the commercial and multi-residential sector over the last 20 years and more. Lighting retrofits are enjoying a resurgence due to LED.
On the other hand, water was pretty much tapped out once toilets using six litres or less per flush became available. Additional savings since then have been marginal. However, water rates that continue to rise by 10 per cent annually will eventually make reuse of grey water and rainwater economically feasible.
Are there low-cost or no-cost measures that could still be more fully exploited?
Automatic controls for lighting and HVAC suffer from a number of challenges:
- poor initial design, installation and/or setup;
- often inadequate documentation and training;
- complexity and poor scalability;
- high degree of drift over time as settings are tweaked to address localized issues by different people with different levels of skill;
- lack of open networking, e.g. some HVAC automation systems and variable frequency drives, or any networking at all, e.g. most lighting controls, making diagnostics difficult;
- no allowance for periodic re-commissioning activities.
As a small-scale example for addressing many of these issues, accessible technology such as the new ecobee3 thermostat is pretty exciting. On a larger scale, low-cost training and re-commissioning activities combined, as appropriate, with the new open technology and better requirements documents will yield improved results compared to the past.
What are the most overlooked energy-saving measures? Why?
Some parts of the construction industry aren’t fully up to speed when it comes to: 1) designing buildings that exceed (or even meet) the bare minimum Code requirements for efficiency and sustainability; 2) ensuring high standards of care and quality throughout the construction process; and 3) delivering meaningful commissioning.
The work often flows down to junior engineers and subcontractors, but they need support, time and complete information to be able to do a good job. The most valuable and perhaps most overlooked benefits of LEED are that it imposes requirements for integrated design, documentation and third-party oversight onto the project team right from the start of a project.
What do you consider an acceptable payback?
Under five years is best for retrofits, but longer is often acceptable where: 1) there are other benefits besides energy savings, such as operational or maintenance savings, or occupant comfort and health benefits; 2) as a package of measures with an aggregate payback of five years or less; and/or 3) for new construction where life-cycle sustainability is a key objective.
What’s more difficult to find, implement and maintain: operational savings or occupant engagement and commitment to conservation?
Maintaining effective occupant engagement over an extended period is definitely very challenging. I appreciate the typical high level of support for sustainability initiatives from Regional employees, but they’re just normal people who have many other responsibilities and can’t spend a lot of time figuring out how to shave a few watts at a time here or there. This is where recent advances in low-cost non-proprietary energy meters and dashboards will prove to be valuable, providing near real-time feedback and compelling graphical presentation.
In bulk metered multi-residential buildings especially, energy sub-metering (combined with individual billing) is still the single most effective energy efficiency measure.
Michael Lithgow is manager of corporate energy services and municipal energy conservation officer in the Regional Municipality of York.