2018 has been a year to remember for SWA’s Party Walls blog. Our consultants have shared their passion for high performance buildings by recounting stories from the field and providing information, new findings, and best practices to improve the built environment.
Whether discussing topics based in New York City or Southeast Asia, here are our fan favorites from 2018…
Installing a dedicated domestic hot water (DHW) plant is a common energy conservation measure (ECM) in the New York City multifamily market. According to Local Law 87 data, approximately 80% of the audited multifamily floor area uses steam heating boilers to produce domestic hot water.[1] A recent SWA analysis of data from steam buildings with tankless coils that implemented this ECM suggests that auditors may want to think twice about recommending this measure widely.
Two unsupported arguments are typically made in favor of installing a dedicated DHW system.
Fun Fact #1: Space heating and domestic hot water generation represent two of the greatest energy end uses in New York State.
Fun Fact #2: More than 70 percent of all New York City buildings utilize steam for space heating.
The clear majority of the distribution systems in these NYC buildings are supplied by high mass steam boiler plants. Digging down a bit further, it is important to note that the most common air:fuel control for these boilers is a mechanical linkage that connects a single servo motor to both the combustion air damper and the fuel control valve(s). We know that adjusting one part of the linkage’s movement affects fuel and air rates elsewhere in the range, making accurate adjustment difficult. We also know that modern linkageless controls use separate servo motors to operate the fuel control valves, combustion air damper, and (in some cases) the flue damper, allowing for finer control.
In fact, SWA recently completed a demonstration study (partially funded through NYSERDA’s Advanced Building Program) to evaluate linkageless burner retrofits on two buildings with respect to energy savings and carbon reductions, as well as qualitative or non-energy benefits. The retrofit materials were funded by Preferred Utilities Manufacturing Corp. of Danbury, CT, who also provided manufacturer’s technical support. The study also focused on quantifying the seasonal efficiency of intermediate-sized, high mass steam boiler plants, which had not previously been studied. The demonstration addresses this gap in the industry’s knowledge.
Welcome back! In Part One we talked about how steam pressure gets too much attention. Controlling pressure for its own sake should never be the end goal—steam pressure is just a means to an end. In this post we’ll discuss one way that controlling steam pressure can be useful—where it can help you balance the system, control the temperature, and yes, save energy.
The biggest issue plaguing two-pipe steam heating systems are steam traps. Steam traps are supposed to do just that—trap steam—keeping the pressurized steam on the supply side of the system and allowing air and water (i.e., condensate) to pass through into the returns. Keeping the supplies and returns separate is critical, but steam traps are too failure prone to accomplish this reliably.
Radiator steam “trap” failed open
At the start of any heating cycle, the system is full of air, which must be removed for steam to enter the heaters. In most two-pipe systems, the steam pushes the air out of the heaters, through the traps, and into the return piping where it eventually exits the system through a vent in a vacuum or condensate tank. That’s what happens when the traps are working. But a failed open trap is no trap at all. It lets the steam flow into the return piping and, with pressure on both the supply and return sides, air is trapped in the system. This affects those farthest from the boiler—the heaters near the ends of the mains and on the top floors—the most. (And with air trapped inside keeping the metal cold, are they even heaters?)
How many of you out there would say you are happy at your place of work? Are you having a hard time concentrating? Now, take a pulse on your surroundings. Are the lights too bright? Are you too cold? Too hot? Do you hear constant humming from the HVAC equipment in the background? How much sleep are you getting at night? How many plants are in your view? Do you even have a view?
I’m sure many of you have heard the statistics that we spend nearly 90% of our days indoors. BUT, did you know that:
When we hear the term “high performance building,” many of us think about energy efficiency first. But, what factors contribute to human health in buildings? How do we design for and maintain efficient building performance without compromising occupant health and well-being? What benefits are associated with healthy homes and work spaces? These are the questions we should be asking ourselves.
Stok report breaking down the cost savings associated with healthy work spaces
Lots of research has been done. Pulling from the LEED, EGC, and WELL concepts, and supported by case studies (specifically Harvard’s School of Public Health’s 9 Foundations and Stok’s report on how workspaces that promote health and wellness), here are SWA’s Top 5 (of 10) tips to effectively address Indoor Air Quality (IAQ) in buildings:
So in utility and policy circles, electrification is all the rage. Grid electricity is getting cleaner (i.e. resulting in lower CO2 emissions), on-site renewables are taking off (sometimes even with storage), and heat pump technologies are getting better. More regional and utility initiatives are encouraging building owners/designers/developers to forego onsite fossil fuels entirely (or at least mostly) to help meet CO2 emission reduction goals. But is electricity really more sustainable than natural gas? Is it cheaper? Which is better, really?
Walking the aisle of your favorite home improvement store, you’ll notice the wide array of options for very efficient light fixtures. Don’t be fooled – truly efficient lighting design is achieved through thoughtful layout and proper controls.
A high performance building warrants an efficient lighting strategy. With so many efficient LED fixtures available on the market, individual fixture efficiency is rarely an issue. However, these fixtures are often placed in high concentrations or at a higher wattage than necessary to adequately illuminate a space. The result is high lighting power density (LPD), which is measured by dividing the total light fixture wattage in a room by the square footage of that room. Even with controls such as occupancy or vacancy sensors, high LPDs are especially energy intensive in frequently occupied common areas, e.g., corridors and lobbies of multifamily buildings, impacting the bottom line efficiency of all buildings.
Projects pursuing Passive House certification are impacted by an optimized lighting scheme more so than a code-built building. As the heating and cooling energy used in a Passive House building decreases due to an excellent thermal envelope, the ratio of lighting energy used increases. Reducing lighting energy use can drastically improve the building’s overall primary energy demand. (more…)
The buildings where we live, work, and play are getting smarter. Even our refrigerators can tell us if we need to buy more cheese while we are at the grocery store. But that’s not what this episode is about. Mostly not.
Today we are talking to David Unger, Founder of Sentient Buildings and an expert in the strategic implementation of IoT technologies that help to create smarter buildings. In an era of data overload, David discusses how his work aims to consolidate and simplify access to information that can improve the efficiency, comfort, and operations of buildings. He also explains why leveraging open communication protocols is the most critical piece to future-proofing your smart building. (more…)
Buying a home can be overwhelming. There are many factors that need to be considered and decisions that need to be made. For many Americans, aesthetics often outweigh certain characteristics critical to a home’s success, such as health, comfort, and efficiency.
To help us evaluate these critical characteristics, we’ve asked SWA’s COO and Mechanical Engineer, Srikanth Puttagunta, to walk us through his recent home-buying experience. Sri discusses ways to maximize a home’s value by taking advantage of incentives, enhancing existing infrastructure, and making the key decisions that may benefit your family’s health and comfort for years come. Join us as we dive into the essentials of single-family home ownership. (more…)
Air-source heat pumps (ASHPs) are a booming business. In the Northeast, manufacturers report that sales of residential systems have increased by 25-35% per year over the past 5-10 years. We’ve seen more and more systems being installed in all types of buildings.
On this episode of Buildings and Beyond, Kelly sits down with her co-host and Principal Mechanical Engineer, Robb Aldrich, to uncover the potential benefits associated with ASHPs and how to get the most from these systems. (more…)