Natural gas moratoriums, consumer demand for fossil-fuel-free homes, Passive House standards: these are among the many reasons why people are increasingly opting for domestic hot water systems powered by renewables. As improved energy codes drive down heating loads, soon the largest load in the home won’t be heating or cooling; it will be the domestic hot water system. This session will explore the options for fossil-fuel-free domestic hot water, achievable in nearly all projects, single family to high-rise, in both new construction and retrofits.

As electrification grows as a tool to reach greenhouse-gas reduction goals, so do the risks of using electricity at times when it is most dirty and costly. To ensure that the benefits of long-term electrificaton of residential buildings are balanced with the short-term impacts on the grid, Massachusetts has begun testing consumer value propositions through tools like the 2017 Peak Demand Management Grant Program, Mass Save Connected Solutions, and the Clean Peak Standard.

If insulation, air sealing, performance testing, and high-efficiency HVAC systems were as exciting to home buyers as granite countertops and walk-in closets, the demand for energy-efficient homes and energy efficiency upgrades would increase dramatically. Home energy labeling allows owners, realtors, and developers a platform to market and value building energy efficiency. It provides a strategy for educating, engaging, and exciting consumers about high-performing home features that lower utilities, improve health and comfort and increase home value.

One of the barriers to implementing high-performance building strategies is the lack of available information for labor costs. Without more information on the costs to build the new assemblies, many builders, architects and homeowners will remain with code-built structures. This session will present multiple perspectives from experienced practitioners on how they estimate retrofit and new construction high-performance assemblies.

The number one obstacle to Zero Energy (ZE) buildings is the perception of increased cost. This session will debunk this myth. Utilizing readily available products, practices and technologies, Zero Energy buildings are being constructed in increasing numbers across Massachusetts. And with the help of state and utility rebates for energy efficiency and renewable energy measures, these projects are being delivered at little or no additional first costs.

Urgent climate goals require state programs such as Mass Save to better target comprehensive decarbonization – applying efficiency, electrification, demand response, and solar+storage – in an equitable manner that addresses differences in local building characteristics. Meanwhile cities and towns, including low income/urban, suburban, and rural communities, are making commitments to local climate neutrality and social equity for their citizens.

Should we be trying to electrify everything? Is it practical for existing and new buildings with the technologies we have now? Two engineers with different takes on these questions will debate electrifying residential buildings, from small single-family to high-rise apartments. Both speakers have years of experience with heat pump technologies (mini-splits, PTHPs, water-source HPs, VRF, and several types of heat-pump water heaters). They’ll present examples of buildings where these systems worked wonderfully, where performance was less than ideal, and a few absolute failures.

Air-to-water heat pumps have generated a lot of excitement for their enormous retrofit potential. This case study details one home’s retrofit to an AWHP system, which was developed by hydronics experts to be simple and repeatable. The project encompassed distribution systems, domestic hot water and backup heat, as well as a ventilation system upgrade from exhaust-only to high-efficiency fresh air (balanced) ventilation.