The ground source heat pump is a wonderful technology that will be vital in achieving energy efficiency goals this century. This technology isn’t new, but it is beginning to become more accepted as a viable solution for large scale, high efficiency HVAC performance. There are two main types of ground source heat pump systems: those that are “Ground Water” (also called Open Loop) and those that are “Ground-Coupled” (also called Closed Loop), see Figure 1 below. In either case, the water from the ground is pumped to a heat pump, where heat is either extracted out of or rejected into the ground and moved into or out of the conditioned space.
As you know, Cx Associates’ work focuses on making buildings perform better for occupants, operators, owners, and for the planet. A common metric we use to assess building performance is the energy use intensity (EUI) which Katie has discussed in her recent blog posts. While attending the recent IEPEC Conference in Denver, I had a discussion with someone familiar with Xcel Energy’s work to be a net zero carbon utility in the relatively near future. We realized that EUI is an insufficient metric for guiding energy program investments at their customer sites. Ultimately, to drive carbon emissions down to a sustainable level that will halt and begin to reverse the climate crisis we are currently in, we need to track energy intensity while also focusing on carbon emissions intensity (CEI) at a building level. Cities and states that have adopted carbon reduction goals will do well to focus on reducing the CEI of their building stock through energy efficiency, fuel switching, and renewable energy generation.
I had never heard of composting as a general practice, until I went to school in Vermont. UVM is one of those places where every trash can is accompanied with a compost and recycling bin (at least when inside near a dining area). When I moved to Boston for a few years after school, I was appalled at the lack of compost availability – what was this madness?!?! Luckily, upon my move back to Burlington, setting up an at home compost was a cinch – just fill up a bucket and drop it off at the waste center every other week for free. While Burlington does a fairly good job of encouraging composting, I just returned from a trip to Seattle where they do curbside compost pick up, and every restaurant I visited had a compost bin…STEP IT UP, EAST COAST!
With a recent move, from the outskirts of Boston back to Vermont (where I grew up), I am rediscovering my love for nature, the outdoors, and taking care of the environment. Shortly after our move, my husband and I began exploring our property to plot out a compost location and now have one that is propped on a stand for easy rotation (which to me, feels extremely fancy compared to the chicken-wire enclosure I grew up with). I also recently discovered the mass transportation system that Vermont offers, which is surprisingly convenient for such a rural area. Taking the bus twice a week combined with having one work-from-home day each week has allowed me to cut down my commuting emissions significantly. Among the other small day-to-day measures we take to ensure we are reducing our impact on the environment, my husband and I take advantage of BeesWrap instead of plastic wrap, reusable silicon sandwich bags instead of the throw-away plastic kind, and eco-modes on our hot water heater (this means quick showers!). Like many (possibly most) others, there is plenty more that we could and should be doing – but we’re working on it.
In a previous blog post, I discussed the energy benchmarking service we currently perform for a healthcare network using the Energy Star Portfolio Manager (ESPM) tool. This tool is used to monitor the energy usage of a building over time. It allows a user to set energy goals, compare the overall energy use intensity (EUI) to a baseline year, and compare the building in question to other buildings with similar use-types and characteristics. In addition to continuing this specific service for the healthcare network, Cx Associates uses the benefits of benchmarking in other areas of our work too. This blog post will discuss what other areas of our work utilize benchmarking and then provide a brief update on changes ESPM has made to their scoring metrics over the past year.
My wife and I have committed to no longer buying combustion engines of any type. This commitment is not easy. It’s not fun either. It is, however, getting easier as time goes on. A recent challenge we faced with this commitment occurred when we realized we needed a new lawn mower. Just try buying an electric lawn mower – not only are their price tags still very much above that of their gasoline-loving counterparts, but you may also pay a hefty price arguing with your spouse about it.
Recently, I have been contemplating the impact of our college teaching styles on the future of our workforce. With technologies and global needs changing so rapidly, what should undergraduate programs foster to prepare graduates for the future needs of the workforce? On a professional level, this has been instigated by our company’s recent search for new employees. On a personal level it comes from being the parent of three young adults who will be entering the workforce in the coming years, as well as discussions with two of my siblings who are college educators.
I recently attended the Performance Evaluation Methodology for Building Occupancy Sensing Systems for HVAC Controls workshop, which followed the annual ASHRAE conference that just wrapped up in Kansas City, MO. The workshop focused on one of ARPA-E’s research programs called SENSOR (Saving Energy Nationwide in Structures with Occupancy Recognition), and brought together a diverse group of individuals, including researchers from national labs and universities, industry representatives, design engineers, and other interested parties.
Sometimes certain parts of the commissioning and retrocommissioning process can seem trivial to both the contractor and the commissioning agent. Of course, the process involves some important and significant checks, such as ensuring the piping design detail matches the as-built piping, and that the specified ductwork sizes match the as-built ductwork size. But the commissioning process also deals with some of the finer details that may not seem as consequential or that have already been checked by multiple parties. So, why would the commissioning agent also need to check it again? In this post I am providing a couple examples of real-world commissioning issues that we’ve found. Each is an excellent reminder of why the seemingly minor commissioning verification steps are still required and important, even though they may seem inconsequential.
Farhad Manjoo’s piece in the New York Times caught my eye recently and struck a chord. It describes the awful wealth gap that is increasing, seemingly by the day, with each newly minted tech billionaire in the San Francisco Bay Area. He reports that despite the fact that “the annual household income necessary to buy a median-priced home [in San Francisco] now tops $320,000,” California lawmakers recently killed Senate Bill 50, which would have undone zoning restrictions in the state. Changing these zoning restrictions would make it possible for more dense housing to be built, thereby increasing the supply and providing some relief to the non-billionaires in California.