One of the biggest advantages that cove.tool has over its competitors is automation. When setting up a project on the platform a user's project location will automatically populate the tool with the relevant local weather data, energy codes information, connect to a cost and carbon database, and more. This article will discuss the key automation done in order to be best compatible with projects from Canada.
In Canada, cove.tool is configured to utilize NECB automatically based on the address of the project. Users can override the automatic configuration and change the standards to adhere to a different energy code, or edit the baseline values to better match their proposed design.
The Canadian energy codes available are: NECB 2011, NECB 2015, and NECB 2017. The platform also includes the option to use the Toronto Green Standard with more energy codes to be added in future updates. Users can also switch to ASHRAE based standards while in Canada if the design team wants to use this standard instead. To find out more about the differences between ASHRAE and NECB, check out this article. The primary differences between ASHRAE and NECB are listed below:
ASHRAE 90.1 mainly considers energy cost and NECB considers energy consumption to achieve compliance.
NECB has stricter policies for a building's thermal envelope than ASHRAE 90.1
For example, after running models for ASHRAE zone 6 (Helena, MT) and NECB zone 6 (Ottawa, ON), minimum compliance for NECB 2015 results in lower energy use than ASHRAE 90.1 2013.
Performance path requires that the building as a whole performs to a certain standard and uses less energy than the same building built to prescriptive code.
Performance compliance shall be assessed through modeling that conforms to specifications detailed in the section 8.4.2 of NECB standard. Currently, the OpenStudio integration feature in cove.tool allows users to use the OSM and IDF files to conduct compliance level energy model for NECB's performance path. Also, future development of load modeling tool will allow for whole-building energy simulation which can be used for NECB's performance compliance path.
TEDI & TEUI
The platform computes TEDI (Thermal Energy Demands Intensity) and TEUI (Total Energy Use Intensity) in addition to EUI (Energy Use Intensity). For those unfamiliar with TEDI, it is the annual heating energy demand for space conditioning and conditioning of ventilation air measured in kWh/m^2/year. TEDI only considers the design aspects that limited the overall demand for heating in a building. By targeting low TEDI, designers focus on passive solutions like good insulation, airtightness, and beneficial sun angles that help reduce energy use directly. For more information on TEDI, check out this article.
TEUI is the sum of all energy used by a building on-site (i.e. Electricity, natural gas, district heat), minus all renewable energy generated on-site, divided by the Floor Area. cove.tool and the SBEC (Sustainable Built Environment Committee) of the Ontario Association of Architects (OAA) came together to build a TEUI Calculator, a web-based app for performance evaluation for Ontario-based projects. The TEUI project aims to simplify the understanding of the objective, measurable performance values of buildings by representing energy and greenhouse gas emissions in three simple and absolute terms, as a function of building area over the course of a year. For more information on the TEUI Calculator, check out this article.
Weather files for Canadian provinces can be found on the Energy Plus website. If the files for the region are unavailable, users may input their own data so long as it is a .epw file type through the loadmodeling.tool.
Cost differences in building material for Canadian users are also accounted for in cove.tool on a per province basis. We source our cost data through field research, leveraging our partnerships with various manufacturers, and by performing literary research using credible and reputable publications. We also reference costs that users have shared. At the moment, that covers 4 categories seen in the optimization tool: wall insulation, glazing assembly, HVAC systems, and lighting systems. Lastly, our costs only reflect bare material cost and do not reflect labor, equipment, freight, taxes, and/or other market-driven premiums which may impact your cost. Learn more here.
Carbon emissions are calculated using carbon emissions factors local to your State, Province, or Country. These factors are applied to the electricity usage of the project and a constant value is used against the natural gas usage. Emissions factors for natural gas and scope 2 & 3 electricity are sourced from Canada's National Inventory Report and from EnergyStar Technical Reference: GHG Emissions.