HVAC systems are often the primary energy consumers in any facility, plant, or building. Conducting a comprehensive analysis of HVAC systems is crucial to conserve energy and decrease carbon emissions. Alongside the environmental costs, economic expenses can also be significantly reduced. HVAC experts are expressing their concerns and providing solutions for achieving energy-efficient solutions to propel progress here.
In the quest for energy efficiency in HVAC systems, the greater emphasis lies on holistic approaches, integration, smart technologies, and operator training. An integrated approach is crucial to achieve optimal efficiency. Improving the efficiency of products may not suffice if the entire system is not seamlessly integrated. The starting point should involve optimising load calculations, as systems are often designed for rare worst-case scenarios that occur once or twice a year. It is essential to explore ways to calculate and reduce the load effectively. Beyond equipment selection, the execution phase is equally vital. Proper system installation and commissioning play pivotal roles.
Components for energy efficiency
Dr. Vishal Garg, University Chair Professor, Plaksha University, notes, “The focus should be reducing the load, addressing components such as fans, pumps, and control algorithms, and optimising chiller efficiencies. Instead of solely focusing on individual components, it is crucial to adopt a holistic perspective when striving for energy savings. People often assess efficiency on a component-by-component basis, assuming that a collection of efficient components will inherently result in an efficient system. However, this is not always the case. A well-designed, properly controlled system with less efficient equipment can achieve commendable efficiency, whereas assembling the most efficient components may not guarantee the desired overall efficiency.”
In the market, various energy-efficient terms are utilised, often in complex and sophisticated ways that may be challenging for the average person to comprehend. Mr. Niraj Shukla, Director, Global HVAC Consultants, added, “In our approach, we carefully consider the three phases, scrutinising how effectively and efficiently the system is designed, how judiciously we select the equipment, and how we operate and maintain it. For instance, in the case of an HVAC system, neglecting tasks such as proper filter cleaning, strainer maintenance, and sensor calibration renders the system ineffective.”
Measurements to reduce energy consumption
Commencing with the right design, it is imperative to consider the building envelope’s role in minimising internal loads. Strategies such as high-efficiency glass can effectively mitigate external heat transfer into the building. Optimising the heat load is crucial rather than relying solely on safety measures. Often, buildings are designed with excessive safety margins, resulting in oversised equipment like 200-ton chillers when a 50-ton capacity suffices.
System selection is equally critical; for instance, Variable Refrigerant Flow (VRF) systems have their applications but are only sometimes suitable. It’s common in the industry to promote new technologies without thoroughly understanding customer needs.
Integration is a significant challenge, especially in India, where many HVAC installations see the HVAC system commissioned while Building Management System (BMS) commissioning lags for years. Incorporating AI can assist in data analysis and predicting system behaviour to enhance control and efficiency. Integrating controls with the overall system is paramount for success.
In India, a significant challenge in HVAC energy efficiency is the presence of three distinct seasons, each requiring tailored system adjustments. Previously, government projects included seasonal commissioning as a contractual practice, but it has diminished. There is a pressing need to revisit and focus on fine-tuning systems for specific monsoon, winter, and summer conditions.
Smart Sensors and IoT
The current demand emphasises a shift in the approach to monitoring, controlling, and managing assets in HVAC systems. According to Dr. Garg, traditionally, BMS systems were expensive, requiring comprehensive initial investment and limiting scalability. However, a more flexible and cost-effective paradigm has emerged with the advent of IoT, cloud computing, and AI/ML analytics. This allows for a gradual start with low costs, offers the advantage of collecting data, as conventional BMS systems do, and enables analytics development. Efficiency improvement involves continuous comparison with a baseline, requiring the identification of this baseline. We can effectively enhance system performance by incorporating fault detection and diagnostics, leveraging the abundance of sensors and computational capabilities.
The supervisor or the person in charge of operations is pivotal in HVAC system maintenance. Mr. Shukla adds that operators are responsible for overseeing and maintaining the system, making them crucial figures in the hierarchy.
Introducing IoT and smart services has proven highly advantageous for these operators. While many parameters and data are collected, the key lies in effectively selecting the relevant ones. A knowledgeable consultant is essential in determining pertinent data and setting parameters accordingly. For instance, in a project involving IoT and smart sensors to monitor filters, a well-chosen set of parameters can accurately predict when a filter needs replacement, achieving an impressive accuracy rate of around 90%.
Mr. Ajaz Kazi, Head – MEP, Reliance Industries Limited, adds, “Incorporating IoT into the system design should be an integral part of the process. Often, the conventional approach involves designing the system first and then considering the addition of IoT elements. However, embedding IoT within the initial design can enhance our understanding of the intended outcomes.”
There is a pressing need to enhance training programs for individuals responsible for facility operations. Establishing test beds or simulators akin to those used in pilot training can provide practical scenarios for facility operators to navigate, identify issues, and implement solutions. The goal is to create an environment where operators can interact with data, understand problems, and learn to address them effectively.
Additionally, developing artificial intelligence-based systems becomes crucial to aid operators in detecting and diagnosing issues. These systems can offer insights into probable causes and assist in making informed decisions. The emphasis should be on establishing comprehensive training environments, whether physical or simulated, accompanied by extensive skilling and training programs.
As per Mr. Shukla, to make information easily accessible and user-friendly for operators, we initiated an exercise in an industry. For each component, we implemented QR barcodes. Operators can scan the QR code to access comprehensive information about the equipment, including troubleshooting videos in their preferred language. This multilingual approach, whether in Andhra, Marathi, Telugu, or others, allows them to understand operation manuals, listen to instructions, and watch troubleshooting videos, making a significant impact. This approach has proven successful, and we’ve received increased orders from companies recognising the value of such skilling and training initiatives.
Furthermore, implementing a reward scheme is a beneficial strategy. Rewarding operators who consistently demonstrate interest in energy-saving practices can be a motivating factor. This could involve establishing an “Operator of the Month” recognition, fostering a positive and proactive approach among operators.
Mr. Kazi notes that several companies attempted to provide cooling services, but trust issues became a major obstacle in India. Payment disputes arose, leading to these companies withdrawing from the Indian market. Trust-related concerns pose a significant challenge in adopting such service models. Regarding skilling, the remuneration offered to operators plays a crucial role. Operators wield significant control over costly machinery, and paying attention to proper training and fair compensation could pose risks. Ensuring competitive salaries and adequate training is vital to attract and retain skilled operators who can effectively manage and maintain valuable assets.
A positive move has been made by the Bureau of Energy Efficiency, which mandated a maximum indoor temperature of 24°C from 2021. Considering that each 1°C increase in summer temperature typically results in a 6% increase in energy consumption, it was necessary. People often kept their indoor temperature at 25°C or higher, but the government’s restriction to 24°C has led to approximately 24% energy savings.
The ratings, such as those provided by the GBC’s ARC software, offer valuable insights into building performance beyond just HVAC systems. For instance, the ARC software tracks daily data input for buildings claiming to be green or platinum-rated, providing a real-time reflection of their status.
Mr Kazi adds, “The Energy Conservation Building Code (ECBC) is taking a step further by developing more stringent star ratings, including ECBC Plus and ECBC Super Plus. The draft is in progress, and once these measures become mandatory, there’s an expectation that compliance will improve. In India, relying solely on voluntary initiatives can be challenging; introducing mandatory regulations will likely drive more widespread adherence.”
The star labelling system, particularly in the residential sector, is an obvious and effective measure, per Dr. Garg’s inputs. Simplifying the process for consumers, the star rating provides a straightforward indicator – more stars denote higher efficiency. This simplicity aids buyers in making informed decisions without delving into complex technical details, such as the materials used in components.
Extending beyond a basic star rating, similar to the approach seen in refrigerator labels, adds an extra layer of energy literacy. Buyers see the stars and understand the expected electricity consumption based on standardised usage conditions. For those interested in deeper understanding, technical details like the Coefficient of Performance (COP) and seasonal energy efficiency are also available. This multifaceted approach enhances energy literacy and empowers consumers to make well-informed choices when purchasing equipment.
Mr. Shukla contributes that there are no specific government policies addressing energy consumption or efficiency in the HVAC industry. However, the government has implemented a mandatory energy audit, the Performance Achievement Trade (PAT) scheme. This scheme requires energy-intensive government companies to register and undergo audits, with HVAC systems included in the assessment. The certificates obtained through this scheme offer a competitive advantage when these companies engage in international trade.
While the government can introduce policies, the key lies in making them mandatory and rewarding to drive action, per Mr. Kazi. Some industry players offer comprehensive solutions, conducting energy audits, designing retrofitting systems, providing guarantees for their effectiveness and promoting and encouraging these companies, where both the customer and the system provider benefit, can create a win-win scenario for all stakeholders, including the environment.
VE (Venture Enterprises) or VIS (Venture Implementation Services) has made efforts to involve various stakeholders in initiatives like the new rating of the Energy Conservation Building Code (ECBC). This involves 25 organisations covering aspects from plumbing to electrical and fire safety. However, the challenge lies in implementation, as not all stakeholders may fully embrace these changes. The government can only enforce compliance in some places, highlighting the need for a collective effort from all involved parties.
Mr. Ajaz Kazi, Head – MEP, Reliance Industries Limited
“Simplicity is key in system complexity, especially considering that individuals with diverse technical backgrounds operate these systems.”
Dr. Vishal Garg, University Chair Professor, Plaksha University
“A well-designed, properly controlled system with less efficient equipment can achieve commendable efficiency, whereas assembling the most efficient components may not guarantee the desired overall efficiency.”
Niraj Shukla, Director, Global HVAC Consultants
“The role of operation and maintenance becomes crucial when discussing energy efficiency. Neglecting tasks such as proper filter cleaning, strainer maintenance, and sensor calibration renders the system ineffective.”