Boiler Plant Upgrades

Boilers provide hot water for space and domestic hot water heating applications. A substantial portion of the total energy consumption in most residential, commercial and institutional buildings is used for hot water heating, as much as 40%.

Improving boiler efficiency results in a reduction of energy consumption and operational cost, while mitigating environmental impacts.

Dirt on heating and cooling coils can have a significant impact on building energy use. Dirty coils reduce airflow, decrease heat exchanger efficiency, and reduce Heating, Ventilation and Air Conditioning system (HVAC) capacity.

In addition, dirty coils contribute to poor indoor air quality and are a major cause of compressor failures in refrigeration systems.

Building control systems, also called Direct Digital Control (DDC) Systems or Building Automation Systems (BAS), can be optimized to achieve low cost energy savings.

The following list of ten strategies outlines commonly identified opportunities in building control systems. These strategies are all noncapital, operational measures that have relatively quick paybacks of less than three years.

In commercial kitchens, exhaust hoods are used to remove the smoke, heat, and odours generated from cooking. To maintain a suitable pressure in the kitchen space, makeup air is typically brought in from the outside to replace the air removed by the exhaust hood. Most kitchen exhaust and makeup fans are interlocked and run at a fixed speed regardless of the level of cooking activity, often 24 hours a day. As such, a large amount of energy is required to condition (heat or cool) this outdoor makeup air flow.

Solar water heating systems harness the sun’s radiant energy to heat water and reduce the amount of purchased energy. Solar hot water systems typically are used to pre-heat domestic cold water before the temperature is boosted in a conventional water heating system. Other applications for solar water heating include heating swimming pools, specialized cleaning processes, and space heating.

In most cases, solar water heating systems result in lower greenhouse gas emissions.

As a hockey fan and a practitioner of energy management, I started thinking… how is Energy Management like hockey? A review of the key roles on a hockey team provides some interesting comparisons.

The General Manager (GM):

The GM determines the direction for the team, assembles the players, and sets the tone for the type of play. Will it be an offensive or defensive style team this year? Will the team be built around one or two superstars or a group of equally talented players? The GM provides the direction for the Coach, player and his management team.
For a successful energy management program, the organizations senior management position (CEO or President) needs to set the tone for the importance of energy management to the organization. He or she demonstrates this through leadership by example. This person communicates and inspires the organization to strive for energy improvements.

The Coach:

The coach organizes the players so that the sum is greater than the parts. He determines which players work best together and builds on the strengths of each. The coach has a strategy and sets objectives for the season, each part of the season and each game. He meets with support staff, players and management to adjust the strategy and deal with challenges that come up. As a facilitator, he tries to get the best out of each player. At many organizations, the “Energy Manager” is the Coach of the Energy Management Team. He tracks the progress each day and moves short term and longer term energy objectives forward. Using the Energy Management Plan as his playbook, he organizes the various parts of the energy team and ensures open communication.
The energy manager solicits feedback from others but ultimately it is his responsibility to move the program initiatives forward. Like the coach of the hockey team, the energy manager is not satisfied with the status quo and is always looking for opportunities to improve.

The Defence:

A strong defence is one of the keys to winning a championship. The defence needs to keep on eye on all the activities happening on the ice and needs to be ready to respond to any lapses in performance of other team members.
For an energy team, the defence is about identifying waste. When are we using energy when we don’t need to? What lighting is on when the room is empty? What computers are on when the computer lab is empty? What room temperatures are set higher than required causing excess heating energy? What walls, roofs, doors and windows have gaps or holes where heat is lost?
The defence wants to keep the puck in the opposition zone, just like the energy management team needs to keep waste down.

The Forwards:

The hockey forward needs to score goals. The focus is on offence — passing the puck to achieve a clear opening to the net and taking your best shot on net. For energy management, the offense is about efficiency improvements.
How can we do better at using the energy that is currently consumed? Replacing equipment with more efficient products and technology is how the energy team scores the goals. It may be through the installation of premium efficiency lighting products, high efficiency boilers, variable speed compressors, or high COP rooftop units.
Some new innovations, like LED lighting, have similarities to the fibreglass carbon sticks available to hockey forwards today: they work better than the traditional wooden sticks, however, they do tend to break in some instances. New technologies go through development cycles and the ones that come out on top are both reliable and efficient.

The Goalie:

The goalie is the last line of defence. If the goalie is distracted, looses focus or not performing, the puck will surely end up behind him. For the energy team, the building operator, security staff or cleaning staff are the last ones around that can prevent waste. They spot the opportunities at the end of the day, week or season.
These individuals are walking through the building and finding open windows, equipment left on, cooling systems running in vacant rooms.
When a high school closes in early July for the summer holiday, are the pop machines, coffee machines and walk in freezers still running? When the retail tenants from the local mall close up on Friday night, do the young staff members know what procedures to follow for the HVAC systems setback and store lighting before they head out for a night on the town. The energy management team needs the goalie to eliminate waste.

The Captain:

Some captains lead on the ice with their performance. Others may be slightly past their prime on the ice but lead in the dressing room by inspiring others to perform. Communication is key for this team leader to motivate others to take action. The energy team needs a captain to lead communication programs as well. He needs to build awareness of the actions others can take to save energy. He needs to provide a reason for change, a consistent message and provide feedback on how the program is doing.
Like the Captain of the hockey team, he needs to know when to fire up the troops and when a tap on the shoulder will do just fine. By communicating a consistent message, the captain of the energy team drives change of the corporate culture by changing one behaviour at a time.

The Training Staff:

The training staff not only keeps the team healthy but also monitors their fitness. Often, they will suggest new approaches to rehabilitation, like the hyperbaric chamber, to keep the players in top form. These members of the team research available nutrition and fitness approaches and stay on top of developments in the field. For the energy team, training is critical to increase competencies.
Some tools, like the online training for building operators that we developed for BOMA BC, is available online to take at their own pace from their own location. Other training for energy management include multiply day training for energy managers, various single day workshops and conferences.
By staying informed and increasing energy management know how, members of the energy team are more effective at managing their resources. Energy management training is a key component of a success program.

The Scout:

The scout is on the road looking at new prospects. Some young players have talent and these are watched closely but they will not all make it to the big leagues. Sometimes the scout takes a chance on a talented player and recommends him for the team. Your energy engineer or manager will be looking for the next round of potential for the energy program as well.
More than likely they are scouting alternative energy opportunities and giving them a tryout. Perhaps a pilot study on solar heating for the local motel that is looking to show customers their commitment to sustainability. Perhaps an office building manager looking as a solar powered parking lot area light or signage. All show promise but only the mature technologies will remain. The energy manager needs to be aware of current and upcoming alternative sources of energy.

The Capologist:

This is a new position in the big leagues as unions and management have moved to limit the spending abilities of the billionaire owners that can not seem to limit themselves (kind of like how my wife limits my chocolate intake). The Capologist knows the numbers- what each player’s salary is, how it adds up to the limit for the team, the impact of injuries on the cap, how trades will impact the teams numbers, and how other teams are doing with respect to the cap as well.
For the energy team, watching the consumption regularly is also a critical role. A monitoring, targeting and reporting system (MT&R) is critical to actively and effectively managing energy use. The energy manager needs to know what the trends have been and why, what has caused recent energy changes, and who to report to.
Like the capologist, he monitors some trends daily, like the electrical demand, and others on regular basis, like monthly energy consumption and costs. Sometime penalties occur, like power factor penalties, late charges, demand spikes and just like the capologist, he needs to take quick action to rectify the situation. Innovative programs such as the BC Hydro continuous improvement program merge MT&R with real time feedback of energy to develop a “continuous commissioning” process.

The Medical Doctor:

Puck in the face? Charley horse? Sometimes players get injured and need some medical care during the game, between games and during the off season. Energy consultants play that role for the energy management team…they bring tools and expertise to help.
Even large organizations with full time energy managers relay on energy consultants and their expertise. The consultant may bring ideas, calculation tools, expertise and knowledge to the energy program. Just like the medical doctor, it makes common sense to bring in the specialists when required.

The Power Play:

It is beautiful to see a power play that clicks: the pucks move crisply from one stick to the next, back and forth until success…a goal! That’s the feeling I have at the completion of an energy project: seeing the result, the savings from the retrofit project, is like the goal on the power play.
This is a chance for the team members to feel good about their work, to celebrate with high fives, and then get down to business as the game continues. Celebrating success is a key component for a long term and sustainable energy management program.

Slumps:

Sometimes even the best teams get into a slump and don’t win every game. Similarly in energy management project, not every project will turn out the way you want it to. Real winners will confront problems and look for ways to make the best of the situation. Strong leadership and determination are required to get back on track.

The Holy Grail:

Every NHL team wants to win the Stanley Cup and every team at the Olympics want that Gold Medal. They focus their energy and work towards this goal throughout the season. Training, teamwork, and focus on the objective are all keys to success. A successful energy management program needs to set goals to motivate, inspire and target.
The goals are shared with others and provide a common thrust for everyone involved. Objectives are then set each “period” so that the goals can be broken down into logical pieces. Tasks are then assigned to members of the energy team to ensure that there are responsibilities assigned with specific time projection.

The Team:

Some of the best players have not won a championship. They try their best but do not have support from others to achieve their ultimate goal. Like a star player, no one individual can achieve success in energy management without the support of others. A university campus needs energy champions in each building to build awareness and share concrete actions with building occupants. It needs maintenance staff to keep condensers clear from debris, filters changed, setpoints optimized. It needs building occupants like faculty and students that are aware of the impact their behaviour has on the campus footprint and care enough to do something about it.
An energy team is made up of individuals with various backgrounds, interests and abilities that come together to make a difference: reducing the environmental impact of their organization.

As you can see, there are many similarities between a hockey team and an energy management program (although it may be tough to sell tickets for fans to come see your energy management team in action). The important point is that just like hockey, it has to be a TEAM effort to achieve the ultimate success. Not just the superstar, not just the players, but a lot of others “behind the scenes” all working towards the same goal.

I hope your favourite hockey team achieves success this year. And I hope that you move forward with all the players on your energy team to enhance your organizations sustainability through smarter use of energy in your facilities.

In the course of those audits, which ranged in scope from a basic energy assessment at a 5,000 square foot bank branch to a detailed energy audit for a property manager of several million square feet of downtown office space, Prism has identified certain key energy savings opportunities at workplace buildings. By looking for these opportunities in their own workplaces, businesses of any size can enjoy significant energy savings and achieve real reductions in their impact on the natural environment – with little or no sacrifice to building comfort.

“Especially in this weak economy, we all need to make sure we are spending as little as possible to comfortably heat, cool, light and power our workplaces, ” explains Robert Greenwald P.Eng., MBA, and President of Prism. “And in the process, when we keep our eyes peeled for energy saving opportunities, we’re also doing our part to shrink our carbon footprints and safeguard the environment. Hopefully, businesses will find these tips a good starting point to launch their own energy savings initiatives.”

Prism offers the following tips to building owners, property and facility managers, tenants, and anyone else who wishes to lean and green their workplaces. Tenants who do not own their own office space or are not individually metered, though less likely to share in the cost savings, are encouraged to speak to their landlords about these recommendations and let them know the value they place on an energy efficient and environmentally sustainable workplace:

1. Be bright about lighting

At the Burnaby Campus of the British Columbia Institute of Technology (BCIT), Prism helped reduce electricity costs related to lighting by $188,000 per year. By having Prism audit their operations and implement a complete lighting system retrofit, BCIT was able to cut electricity consumption by 11% (i). That project included installation of electronic ballasts, compact ?uorescent lamps, LED exit signs and occupancy sensors to ensure that lights automatically turned off when space was unoccupied. However, regardless of the size of your operations, being conscious of how lights are used and aware of the latest available lighting technology can make a big difference to the bottom line. For example, simply lowering or turning off lights when daylight is available can significantly reduce consumption. By replacing incandescent lighting with LED pot lights or induction lighting (which is four times as efficient and lasts over 40 times longer than incandescent bulbs) in lobbies and atriums, electricity consumption and greenhouse gas (GHG) emissions can be substantially decreased. In every case, visual comfort must be balanced against aesthetics and operating costs.

2. Get HVAC on track

With optimal use of the control systems for a workspace’s heating, ventilation and air conditioning (“HVAC”) equipment, significant energy savings can be realized. Building operators can be trained to adjust room temperature set points to balance comfort with efficiency. As well, proper use of controls can allow for holiday and weekend shut down. Settings can also be used to make sure that workspaces are warmed up slowly and in advance to avoid costly spikes in energy usage at the beginning of a winter work week. All of these programmable settings can allow for manual operator override. Also, the use of variable speed drive (VSD) pumps and fans in HVAC systems can add to the savings. While the size of a pump or fan for HVAC systems is typically chosen based on peak demand (e.g. during the hot summer months), VSD pumps and fans allow for slower pump and fan speeds during low demand periods. A 10% reduction in pump speed and ?ow can translate into a 17% reduction in energy consumption. When a local property management firm hired Prism to conduct energy audits at 13 of their Lower Mainland office buildings, Prism identified potential annual savings of over $85,000 by simply upgrading HVAC controls and educating operators on the optimal use of control systems.

3. Operate and purchase office equipment with an eye on energy savings

Too often during audits, Prism finds that office computers’ power-saving or “sleep” settings are not properly set or not used at all. Other times, the IT department insists on employees leaving computers on to run updates overnight. By teaching employees to properly use the sleep settings and by challenging IT to come up with alternative solutions (e.g. running the updates on weekends only), computers can be shut down, or at least put to sleep, when not in use overnight, on weekends and over holidays. While the energy savings ROI of replacing an old copier or dishwasher with a new energy efficient one may be too long to justify an immediate purchase, when a unit reaches the end of its useful life, make sure that it is replaced with the most energy efficient model available within your budget, that meets your office’s needs. When Vancity, Canada’s largest credit union, was looking for help developing an energy policy, their Facilities Management Department hired Prism. The resulting plan set a course of action based on sound conservation and energy management practices, application of new energy-efficient technologies, and employee education and training. The policy’s equipment purchasing guidelines (as well as lighting, HVAC, and water-conservation strategies) assisted Vancity in achieving their stated goal of “carbon neutrality by 2010” a full 2 years ahead of schedule on December 31st, 2007.

4. Monitor and evaluate your energy and utility costs

When Prism monitored Air Canada’s utility costs for their facilities across Canada, they discovered billing errors in the amount of $464,000 at their Richmond facility, which was then refunded by the utility(ii). As well, by monitoring a business’ energy bills, a pattern of usage can be seen. The HVAC controls can then be set for optimal efficiency and comfort during peak and low demand periods. Due to the large potential savings afforded by monitoring clients’ energy and utility costs, Prism has developed specialized on-line tools to allow clients to monitor, target and report against their energy and utility consumption. Also, by monitoring the savings achieved by their energy efficiency measures, businesses can keep an eye on their progress as they look for additional savings opportunities.

5. Employee buy-in key to success

Through their years of experience, Prism has learned that unless employees have “bought into” the initiative, efforts at greening and leaning a workplace will not produce optimal results. Even the newest, most efficient energy-saving technology can be easily overridden by employees who are not invested in the program. In order to create and maintain a culture of energy efficiency, employees must be properly trained, made aware and reminded of the goals of and purpose behind the initiative. With that in mind, Prism has been delivering energy management training of behalf of Natural Resources Canada for over 10 years including their “Energy Monitoring” and “Spot the Energy Saving Opportunities” workshops. Prism has also developed an online energy management course for Building Owners and Managers Association (BOMA) building operators in BC.

“It’s been our experience that once employees are properly trained and feel they are critical to a program’s success, many of them become highly motivated to find new ways to improve and build on the results achieved. That enthusiasm can generate remarkable energy savings,” adds Greenwald.

Robert Greenwald, President of Prism Engineering
Sarah Smith, Social Marketing Program Coordinator at Prism Engineering

Successful energy management goes beyond simply knowing which equipment to buy and how to properly set controls. Effectively managing the energy performance of advanced education facilities requires a holistic approach. This method takes a broader perspective and looks at the whole energy management picture, including the organizational, technical and behavioural aspects. It also requires a broad organization-wide commitment to continuously looking for ways to improve. This article outlines eight key areas critical to successful energy management, using examples and case studies from Langara’s energy management program.

Organizational

1. Getting Commitment

Incorporating energy management practices into any organization requires senior level management support and commitment. Without it, saving energy will not be seen as a priority and any program goals, targets, plans and initiatives will lack the necessary support to see them succeed. Securing commitment from senior executives in the beginning of the process will help ensure the success of all energy management initiatives, from retrofit project financing to staff engagement programs.

Secure senior management commitment by demonstrating how energy management ties in to your organization’s business strategy. Energy management offers quantifiable cost savings and provides opportunities to engage staff, students, and faculty. It can also position the organization as a progressive industry leader making a positive difference in the local community, and globally, through its commitment to environmental sustainability.

2. The Importance of a Plan

An energy management plan formalizes the organization’s commitment to energy management and provides a means of communicating this commitment to staff, students, faculty and community stakeholders. A plan establishes a framework for identifying energy efficiency opportunities and a benchmark for monitoring future performance. It also clearly lays out energy management roles and responsibilities.

An effective plan provides information on energy-use, sets goals and targets, outlines energy saving opportunities and includes financial analysis of proposed actions. As well, the plan should include strategies for engaging and communicating with staff and students and provide opportunities for staff training. An effective plan will also outline how energy use will be monitored and reported.

3. Integrate Energy Management into the Organization

Ideally, energy management should be fully integrated into all aspects of the organization. Begin by developing an understanding of your organization’s current operational management systems and identifying which policies relate to energy management. Understand how energy management fits into the organization’s overall corporate strategy and how best to connect energy management with other campus activities. Explore opportunities to link energy management practices with existing courses and programs, or look to develop new classes that provide students with hands-on learning experiences.

Technical

4. Energy Projects

As all energy management programs invariably include technical aspects, it is important to plan strategically by identifying technical opportunities and priorities. Be ready to take advantage of new funding sources that may become available by having a “shovel ready” list of projects.

Start by developing an understanding of your organization’s current situation and energy usage. Look at the cost structure of your bills. Compare your energy use to that of similar organizations in the education sector and benchmark the performance of your buildings. Identify when and where you use energy. Once you have collected this information, you will be better able to identify savings opportunities by eliminating waste, maximizing efficiency and optimizing your energy supply. To eliminate waste, consider optimizing set points for heating and cooling, installing occupancy sensors for lighting and HVAC systems, or optimizing schedules to reflect building occupancy patterns. Next, look for opportunities to improve the efficiency of your building’s systems. Purchase Energy Star rated equipment, premium efficiency motors or condensing boilers and ensure filters are always properly maintained.

The next step in identifying energy saving opportunities is to optimize your supply. This means considering alternative energy options, such as geo-exchange, heat recovery and solar opportunities. Langara College recently designed and built a new library building, which features several of these energy alternatives. The building is designed to be 71% more energy-efficient than the baseline established in Canada’s National Energy Code for buildings. It features several innovative ways of saving energy in new building projects. For example, the library is naturally ventilated – five wind towers pull air upward through the building and the undulating concrete roof boosts the pulling power by increasing wind velocity. Remotely-controlled windows open to bring air into the building. A geo-exchange system and water source heat pumps cool and heat the interior. Waste heat is captured from exhaust air and the building’s exposed cast-in-place concrete and high-performance glass further aid in energy transfer and storage.

5. Financial

When making the financial case for a retrofit or new building project, it is important to look beyond annual savings and consider the long term value of the project. At Langara College for an example, the energy management savings from a 2001 retrofit have been $50,000 per year. However, it sounds more impressive to say that the cost avoidance has been over $700,000 since 2001. The long term savings figures will help build a better business case for a project.

Behavioural

Technology is a vital part of energy management. Ultimately, however, it is people who control, use and save energy. Providing effective training for key staff and finding ways to fully engage all staff, students and faculty members in energy conservation programs is critical to successful energy management.

6. Training

An effective way to improve energy efficiency in buildings, is to provide training for those in the organization who work directly with the buildings’ energy systems. Training should provide building operations personnel with the skills and knowledge to properly manage and maintain equipment, to identify energy savings opportunities, and to implement operational changes. As well as providing them with enhanced knowledge and critical tools, by building up competencies in your staff, you enable them to take ownership of, and pride in, the energy management program. This sense of ownership often turns them into your organization’s ‘energy champion’ – always on the lookout for new ways to improve efficiency and save you energy.

7. Awareness and Culture Change

Many organizations find that engaging students, staff and faculty in energy efficiency and conservation programs is an effective, low-cost way to begin saving energy, or to strengthen existing energy practices. The challenge is to find out why people behave the way they do, and how to best encourage them to adopt new behaviours. The most effective awareness and behavioural change programs are the ones that capture the imagination of students, staff and faculty and effect widespread cultural change within the organization. The ultimate goal is to get everyone on board and harness the power of small daily behavioural changes. Eventually, behaviours such as turning off lights and computers when they’re not being used, using day lighting instead of artificial light, and wearing a sweater to stay warm instead of turning up the heat will simply be considered the norm. “Langara Thinks Green” is a campaign to encourage students, faculty and staff to ”protect and enhance the environment for future generations, and to use and manage Langara’s own physical environment in ways that lead to sustainability’. Langara’s website provides green tips and information on how to get involved in green programs on campus. They have also developed a Sustainability Pledge, which allows students, faculty and staff to commit to specific energy saving behaviours.

Continuous Improvement

8. Monitoring, Targeting and Reporting (MT&R)

Monitoring, setting targets and reporting on energy use is a crucial element of any energy management program. However, the process must go beyond mere data collection. Detailed analysis of the data is needed to meaningfully report on achieved savings and to properly demonstrate opportunities for energy conservation. Presenting key decision makers and stakeholders with compelling energy information, in a clear and timely manner, encourages people to take action and is an effective way of demonstrating the results of energy management initiatives. This helps to reinforce the benefits of the program, as well as to inspire participants and maintain their interest. Finally, continuously monitoring, targeting and reporting on energy use creates important feedback loops for the organization and helps to support a culture of continuous improvement.

In 2010, Langara College installed sub-meters on electrical and gas utility meters to get a better understanding of energy distribution and use. As a result of this information, the College will be setting energy performance targets for each building.

Thinking Holistically about Energy Management

Taking a holistic approach to energy management will help you set achievable and realistic goals, ensure you have the commitment and support necessary to carry out projects and programs, and inspire a campus-wide culture of energy saving. This approach is so critical to successful energy management that the International Organization for Standardization (ISO) is in the process of approving an international standard (ISO 50001) for integrating energy management into organizational procedures and management systems. This standard, if widely adopted across economic sectors, and could influence up to 60 % of the world’s energy use. Whether adopting the ISO standard or another energy management approach, the success of any energy program will depend on the eight key areas identified in this article.

… and how Prism Engineering carefully addresses each one.

Prism Engineering conducts an average of 50 energy audits a year.  Our highly-trained energy, electrical and mechanical engineers and technologists devote a great deal of their time and effort to conducting energy audits at commercial, institutional and multi-unit residential buildings.  So when we heard that the February 2011 issue of the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) Journal featured an article entitled “The 10 Most Common Problems in Energy Audits,” our ears perked up.

Ian Shapiro, the article’s author, was interested in why some energy projects achieve substantial savings while others do not. He looked to energy audits for possible explanations and found 10 common issues that greatly affect a project’s ability to deliver on promised savings. The study conducted a high-level review of 300 US building audits and then looked in detail at 30 of them: 15 commercial and 15 residential. Below, using the framework set out by the ASHRAE article, we review these 10 industry issues and explain what Prism is doing, in each case, to ensure that our audits remain as reliable, informative, and valuable as possible.

#10 Inadequate Review

Obvious mistakes other than calculations

The 10th most common issue with energy audits are non-calculation errors due to inadequate report review. This would include mistakes such as duplicating sections of reports, or making the assumption that a condensing boiler is automatically over 95% efficient. To avoid these kinds of obvious non-calculation errors, Prism follows a comprehensive quality assurance and review process. All reports are written using the newest version of our energy audit template. This avoids duplication or misnomer errors. After an energy report has been drafted, the report is reviewed by Prism’s Senior Energy Engineer, Ken Holdren. He begins with a detailed review of all calculation spreadsheets and then gives the report a thorough read-through for grammar, terminology and clerical errors. Ken, who has been with the company for nine years and has 30 years experience in the field, mentors Prism’s energy audit team and is responsible for quality assurance of all energy management projects.

# 9 Energy Savings Estimation

Overestimation of energy savings

When making energy savings calculations, it is impossible to account for all factors that affect energy savings. However, Shapiro found that over half of the energy audits studied had savings that were twice as high as could be reasonably expected. At Prism, we are carefully conservative about our estimates. This approach reflects the complex nature of building systems and the effect that the people occupying these spaces and managing these systems can have on the results. High energy savings estimates can create unreasonable expectations and may lead to poor prioritization of measures.

Last year, BC Hydro conducted an independent review of Prism Engineering’s energy audits and found that, on average, 87% of calculated savings were “approved”. The balance may have been realistic but exceeded the thresholds set by the utility. By using hourly bin models to calculate savings for all weather conditions, and equipment data sheets and part load efficiencies to accurately model the energy consumption of major building systems, we are able to predict with a high degree of accuracy how much energy each measure can actually save our clients. Using these tools helps prevent assumption bias errors and errors due to poor modeling. Our tools are either developed in-house, or by reputable organizations such as the US Department of Energy or Natural Resource Canada. They are updated regularly based on feedback from our trained energy auditors and our continuing experience in the field.

#8 Billing Analysis

Inadequate billing analysis for measures and projects

Over half of the energy audits that Shapiro looked at did not include adequate billing analysis. While the ASHRAE Standard is to study at least one year of monthly data, Prism typically analyzes three years worth of energy data. This gives our clients a better understanding of the consumption patterns and energy costs of their buildings. We are able to run better regression analysis (a statistical technique used to determine the relationships between variables in order to predict future energy use) which allows us to properly understand how variables that affect energy use, such as weather or occupancy patterns over a particular period, affect energy consumption. This provides us and our clients with a baseline standard against which to measure energy consumption in subsequent years.

#7 Building Description

Building components poorly described or missing entirely

All energy audits should include a detailed description of all components of a building. Description and analysis of some components listed in Shapiro’s article are more applicable to commercial and industrial buildings, while some are more appropriate for residential energy audits, such as infiltration, windows and wall/roof components. Prism focuses on HVAC and lighting systems for commercial, institutional and multi-unit residential buildings, because these are the systems that typically offer the best opportunities for energy savings in these building types. Our energy reports provide a detailed description of all major energy consuming systems and equipment in a building, based on all available information collected and observations made by trained energy engineers during site visits.

#6 Installation Costs

Installation costs underestimated or omitted

It is crucial that installation costs are properly reflected in the energy savings calculations. If no installation figure is provided for the implementation cost, there is a good possibility that the measures will be prioritized incorrectly and a more expensive project could be selected over a more cost-effective one. Furthermore, energy audit reports often provide an initial budget for implementing selected measures. If the installation cost is missing or underestimated, the project would be at risk of going over budget. Our installation cost estimates are based on 20 years of industry experience and the knowledge base of our diverse team of energy engineers. We are careful to conservatively estimate installation time, ensure that we have current quotes from suppliers, estimate any available incentives, and include all applicable engineering costs.

Installation costs are critical to the decision making process, but can be difficult to properly estimate because of fluctuating prices over time and between suppliers. We achieve a high degree of accuracy on lighting retrofit costing by having a detailed costing database. Developed in house, this tool helps our lighting team identify retrofit opportunities, model scenarios for different lamp and ballast options, and calculate payback for various alternatives. A recently implemented lighting retrofit measure at a B.C. university identified 800,000 kWh of projected savings, a 30% reduction in lighting energy costs. Using the database to calculate implementation costs, the project came in under the projected budget by 10%. Through conversations with our staff, we have discovered that we can provide even better information to our clients by creating an installation cost database for all mechanical systems and equipment types. Plans are underway to develop this tool with help from our mechanical department.

#5 Energy Savings Measure Selection

Selecting the wrong measure due to missing or incorrect information

The most common reason that energy auditors do a poor job of identifying and recommending energy saving measures is due to missing or incorrect information. According to the article, one of the most common errors is to recommend a measure with a longer payback than the expected life of the project. Other errors happen when energy auditors make biased assumptions, do not use life cycle costing, or underestimate equipment or installation costs. Our tight quality control process helps us catch potential mistakes and ensures that we are making good recommendations to our clients. The process begins with a well developed report template, includes careful calculations based on accurate data, and ends with a thorough final review by our Senior Energy Engineer.

#4 Life-cycle Costing

Failure to provide client with the “whole picture” afforded by Life-cycle costing

Unlike simple payback, life-cycle costing provides a holistic perspective on potential measures and helps clients and energy auditors make better decisions about which projects to pursue. In our energy audits, in addition to providing simple payback metrics, we also calculate the Internal Rate of Return (IRR) and Net Present Value (NPV) for all measures, as well as for the report as a whole. All of these figures are captured in a high-level overview table in the report summary to allow for easier decision making on the part of the client. This information helps our clients make the most effective business case to senior management, for the implementation of the energy savings measures. We also include various options for utility rates, such as ‘no price escalation’ and ‘2% annual price escalation’. We can’t predict the future but we can provide reasonable models for possible scenarios.

#3 Equipment and Project Life

Overestimated or omitted

Because equipment or project life is so critical to accurate life-cycle cost analysis, Shapiro included this issue among his top three. Missing or incorrect information regarding project life can lead to poor measure prioritization. At Prism, we include project or equipment life in all of our NPV and IRR analysis, calculating it for every measure we recommend.

#2 Scope of Opportunities

Weak description of scope of measures

We provide our clients with all pertinent details about a particular measure in our energy reports, including the location, quantity of items needed, and the energy rating of the equipment. All of our reports include an explanation of the measure intent and a list of assumptions used in the calculations. We also provide design schematics for the more complex measures. Although Shapiro recommends including testing requirements, we don’t often include this information in our reports. Given that some of our clients implement measures on their own after receiving our reports, we have decided to explore, with feedback from our clients, whether to include testing requirements in future reports.

#1 Missed Opportunities

Neglecting key opportunities

The most widespread problem in energy audits as identified by Shapiro is missed opportunities. Shapiro argues that comprehensiveness is widely recognized as a critical feature of all high quality energy audits. He provides a list of opportunities which he feels should be covered in every energy audit: high-efficiency HVAC, domestic hot water and lighting; lighting power density; lighting controls; wall or roof insulation; motors/drives; HVAC controls; and fenestration opportunities. While we agree that all energy audits should provide clients with a reasonable selection of options for implementation, his study combined results from energy audits of both residential and commercial buildings. In the context of Vancouver’s mild climate, building envelope opportunities for commercial buildings such as fenestration measures or wall and roof insulation do not offer good returns and are sometimes difficult or disruptive to implement. These types of improvements are more appropriate for mid-to-small scale residential buildings. This list, therefore, might not be entirely relevant to clients with commercial, institutional or large-scale residential building portfolios who are trying to determine the comprehensiveness of an energy audit.

Prism has over 20 years of experience working with industry and commercial sector clients. The information in our energy audits is the result of careful study, precise calculations and meticulous review. Our reports are comprehensive in scope and allow our clients to make better decisions about proposed energy saving projects. Through site visits and client consultations, we spend the time necessary to really get to know our clients’ buildings’ systems. Our calculations and energy savings models are based on well-developed tools and our energy audit report template helps ensure we do not miss any opportunities. Despite the numerous systems we have in place to avoid these industry problems, we are always looking for ways to improve our audit process. Our team of highly skilled and well-trained energy staff at Prism Engineering strives for continuous improvement of our tools and services, in order to better help our clients save energy.

Top 10 Retro-commissioning Opportunities Found In Your Building
With LEED and other building certification programs pushing the ‘energy efficiency’ envelope, building owners are constantly looking for ways to upgrade their older building stock in order to optimize occupant comfort while lowering utility bills. The challenge is knowing which operational changes and retrofit projects will yield the best results.

Retro-commissioning helps pinpoint specific opportunities to improve a building’s overall performance. Retro-commissioning studies can help resolve problems that occur during design or construction, or help address issues that may have developed over the course of a building’s lifetime.

To help building operators understand the types of opportunities that may exist in their buildings, we have compiled a list of the “Top 10 Retro-commissioning Opportunities”, commonly identified in our Retro-commissioning studies.

10. Eliminate Passing (leaky) Valves

Our engineers have found that passing valves that control heating or cooling coils can result in unnecessary energy consumption. The following conditions can interfere with a valve’s ability to fully stop the flow through the coil when in a closed position: an improperly connected, aligned or adjusted actuator and valve; insufficient seat load; debris or other contaminants caught in the seating surface; and equipment wear and tear.

9. Add or Improve Chilled Water Temperature Reset

We regularly find chillers operating at fixed supply temperature set points, rather than according to the building’s actual cooling demands. Increasing the chilled water supply temperature will improve the chiller efficiency. This can be achieved by revising the DDC system to provide chilled water supply temperature reset based on cooling valve positions, high temperature variance, or outdoor temperature, depending on the application.

8. Volume Control for Pumps and Fans

It is a common practice to install variable speed drive on pumps and fans in variable volume systems. However, inefficiencies result in the system when speed drives are continuously running at high capacity. This can be caused by excessive pressure set points, critical zone reset algorithms that do not address rouge zones, air intakes clogged with debris, operator overrides, and many other causes. Modulating pumps or fans to deliver the required flow will save energy.

7. Optimize Ventilation Rates

Optimizing ventilation rates in air handling units provides further opportunities for energy savings. For instance, an air handling unit serving a gymnasium could be outfitted with occupancy and carbon dioxide sensors which would provide demand controlled ventilation and maintain minimal outdoor air when there is limited or no occupancy.

6. Eliminate Unnecessary Lighting Hours

Even when building lighting control systems are programmed by a schedule, lights will occasionally remain on when the space is unoccupied. To minimize lighting hours, require the first person using the space to manually turn on the lights and set up the system to sweep off the lights at fixed intervals after normal occupancy hours.

5. Optimize Zone Temperature Set Points

When a system is programmed to satisfy the highest cooling demand in a space, a single zone with low set point can set the system in full cooling mode, while reheat coils serving other zones are open to provide heat. To rectify the situation, avoid having one zone dictate the supply temperature, limit the range of occupant temperature reset, and follow up by investigating the root cause of the problem.

4. Optimize Supply Air Temperature

Another energy saving opportunity is found when the supply air temperature set point is fixed instead of being on a reset schedule. In some cases, the set points are chosen based on the operator’s desire to minimize complaints. In order for the system to run optimally, temperature must be adjusted based on the actual requirements of the spaces and occupants.

3. Eliminate Simultaneous Heating and Cooling

Eliminating simultaneous heating and cooling offers an important means of reducing energy consumption. One prime example is when a Variable Air Volume (VAV) system is delivering a low supply air temperature but all the VAV boxes downstream are in heating mode. Another occurs when the building has a mix of DDC and pneumatic controls. With the pneumatic thermostat controlling the hydronic baseboard heaters and a DDC space temperature sensor controlling the VAV box, the same space may be simultaneously heated via the baseboard and cooled from overhead.

2. Optimize Economizer Operation

Our engineers often find economizer dampers that are failed in minimum position (which results in inadequate free cooling), incapable of full closure, or lacking full range operation. This often occurs with aging actuators and damper bearings that are overdue for maintenance.

1. Reduce Equipment Runtime

The most prevalent opportunity for increasing energy efficiency in buildings is reducing equipment runtime. In our experience, equipment is often left on by accident or by decision of the building operator. Instead of simply restoring the auto or scheduled running times, we work with the building operator to address the root cause of the problem, which yields better long term results. Use energy monitoring information to identify opportunities to reduce equipment runtime. Often, DDC schedules are not aligned with statutory holidays. The DDC system should be programmed to reduce equipment runtime, as when in unoccupied mode.

Our engineers, and the operators that oversee their buildings, use a variety of tools to assess and monitor a building’s energy performance. These tools include energy profiles, DDC trend logs, DDC graphics (for quick troubleshooting and verification), exception reports that generate alarms, and CUSUM analysis to track energy savings.

This list of Retro-commissioning opportunities is focused on restoring a building system’s optimal operational conditions. They are all non-capital, operational measures that have relatively quick paybacks of between one to three years. Ultimately, compared to the cost of wasted energy, additional maintenance, and equipment downtime, Retro-commissioning studies represent an excellent investment and offer an extremely cost-effective way to enhance the energy performance of existing buildings.