The State of Minnesota Sustainable Building Guidelines are a component of a larger project of the Departments of Administration and Commerce called "Buildings, Benchmarks and Beyond" (B3).
The Baseline in B3 Benchmarking is used to compare an Organization or Site’s current consumption to a Baseline Year. The Data Owner for an Organization selects a Baseline Year, and the B3 Reporting section displays the current consumption compared to the weather-normalized Baseline Year.
Weather Normalization removes the variable of weather in the comparison, so you know that a reduction in consumption is due to operation or changes in the building systems, not the weather.
B3 Benchmarking automatically creates an energy Benchmark for each Site in an Organization. The Benchmark is a prediction of the Site’s consumption based on an engineering model of the Buildings, constructed as if each Building were built to the current energy code. Actual consumption of the Site will vary from the Benchmark. If the variance is large, you should check all your Building data.
The Benchmark is designed to be a good screening tool to identify Sites that need attention. Sites that use more energy than the Benchmark are good candidates for an energy audit.
A Building in B3 Benchmarking is a physical structure that is greater than 5,000 square feet and has more than one fuel source (Meter).
B3 Benchmarking allows the user to see consumption in three different formats, or currencies:
- Carbon Emissions
Each of these views is valuable in its own way.
A Data Owner is an individual with a B3 Account that is responsible for an Organization. This person receives Meter Reading Reminders as well as the Seasonal Improvement Report.
Hours of Operation
Hours of Operation is the total time in which the majority of employees, students, shoppers, etc. occupy the building. Users define this time by indicating the average hours per day, days per week, and months per year that the building is occupied. Hours of Operation is not the number of hours in which the buildings systems (HVAC, etc.) are running and does not include the ‘after-hours’ time in which cleaning or maintenance staff are the only people in a building. Instead, this time is the number of hours in which a building is typically “open” and majority occupied. For example, the Hours of Operation for a school are 7:30am to 4:30pm (9 hrs/day, 5 days/week, 9 months/year), which includes instructional time and after-school clubs and sports practice time. On the other hand, the Hours of Operation for a city hall staffed and open to the public during business hours would be 9am-5pm M-F and 9am-2pm on Sa. (average 7.67 hrs/day, 6 days/week, 12 months/year).
A Meter in B3 Benchmarking is a physical meter on Site, usually used for billing. Current Meter types are:
- Natural Gas
- Chilled Water
- Steam/Hot Water
- Fuel Oil
- Electric Renewable (Wind and PV)
- Potable Water
- Sanitary Sewer
- Storm Water
Each Meter has a collection of Readings. Users must specify a Utility for each meter to enable carbon calculations.
A reading is a measurement of consumption and dollars for a period of time. Most Readings will be information entered from a utility bill. In order to avoid gaps, the Start Date of each Meter Reading should be the same as the End Date of the previous reading. Readings do not have to be entered in chronological order. You can enter a new Reading for any time period, and resort the Readings chronologically.
An Organization in B3 Benchmarking is a public entity that has one or more public Sites. Sites may belong to one and only one Organization.
Potential Savings are rough estimates meant to provide a sense of the magnitude of savings possible for buildings. They are calculated by taking the number of potential MMBTU savings, which is the difference between 85% of annual energy consumption of the Benchmark and the actual usage, and multiplying it by a cost factor.. 85% was chosen, because a significant number of buildings are able to reduce consumption below 85% of the expected Benchmark modeled annual consumption. The cost factor is calculated by looking at the weighted average energy cost by energy type per MMBTU for the entire portfolio of buildings in B3. For example, if 50% of the MMBTUs in the system used electricity, 50% of the factor is the cost of electric MMBTUs. This also means that all energy types are part of the factor from propane to district hot water, but in proportion to that of the entire B3 Benchmarking portfolio.
A Sector is a categorization of Organizations. There are currently five sectors, in B3 Benchmarking:
- Higher Education
- Public Schools
Each Organization in B3 Benchmarking belongs to one and only one Sector. We may add additional sectors in the future.
A Site is a collection of Buildings and Meters. B3 Benchmarks are created at the Site level. A Site in B3 is most often a single physical location or campus.
Buildings in B3 are described using Space Usages. A Building may have more than one Space Usage (e.g. 50% Community Center and 50% Office). Each Space Usage contains data about the occupancy, percent heated, and percent cooled, that can be modified by the user. It is important to enter accurate Space Usage data. The better the data entered, the more accurate the Benchmark.