Large commercial and residential buildings must overcome various hurdles before implementing deep retrofits or capital projects that help achieve building decarbonization. In this section, we go through a list of technical barriers and questions often faced by building owners and retrofit project developers.
Access to Occupied Spaces.
Lease Concerns.
Regulatory Limitations - Rent Stabilized Apartments
- The building owner is required to provide free heat and hot water.
- No mechanism to recover investment in new systems is necessary to achieve decarbonization.
- Buildings are capital constrained
Split Incentives (tenants pays for energy).
Work must be completed at the end of facade/window useful life; very long usefullife
Building Code
Glazing Reduction at odds with aesthetic/marketability concerns
Difficult installing with occupied spaces
Reduce Local Law 11 recurring cost via overcladding
- Aesthetic Concerns
- At odds with historic preservation
- Capital intensive
- Lot Line Limitations
Technology Limitations
Need higher R-value/inch for thinner wall assemblie:
Vacuum insulated panels
Aerogel panels/batts
Zero-GWP blowing agents for closed cell spray foam (nitrogen blowingagent needs to be more widely adopted)
Energy Recovery Ventilation (ERV)
- Space Constraints
- System Tie-in point accessibility/feasibility
Rooftop Supply Air (Reznor) Unit Alternatives
- Heat Pump Alternatives to eliminate resistance heat
- Combine with ERV
HVAC Load Reduction (HLR) Technology
- Vent or Capture Exhaust Gases
- Space Constraints
- System Tie-in point accessibility/feasibility
Central vs. Decentralized Ventilation Systems
Direct Outside Air System (DOAS)
Modular Perimeter Ducted Air Heat Pumps:
- Competition for Leasable Space
- Space Constraints
Ventilation Points-of-Entry
- Aesthetic Concerns
- Lot Line Facades/Building Setbacks
- Competition with Leasable Space
- Space Constraints
Variable Refrigerant Flow (VRF)
- Fire and Life Safety concerns over volume of refrigerant gas located withinoccupied spaces.
Regulatory Risk from new refrigerant policies
PTAC and VTAC
Ducted Supply/Exhaust Air Source Heat Pumps
Domestic Hot Water
Central DHW Systems:
- Limited domestic production
Performance not confirmed by independent third-parties
- More demonstration projects needed
- Decentralized DHW Systems
More open source interconnection between devices/interoperability is needed toachieve energy distribution flexibility and capacity expansion:
- air source that has a manifold connection to interconnect with water source orrefrigerant gas distribution
- interconnectivity/simplified heat exchange between refrigerants/water/air, etc.
- Other optionality and add-ons
multi-purpose technology for heating, cooling, heat exchange and ventilation, filtration,and/or domestic hot water
Domestic production and supply chain is limited
Small players operating in this space
Technology is not tested over long operational periods
- Daikin, Nilan, Zehnder, Drexel und Weiss, Minotair, Build Equinox, Clivet
Green Hydrogen
Renewable Natural Gas
Biofuel
Biomethane
REC Purchasing
- NYSERDA monopolizes REC purchasing from renewable energy projects
Deployment timeline is highly uncertain
Price per ton of carbon is highly uncertain and will likely be volatile/low based onprevious emissions trading scheme outcomes