If you manage a large portfolio of buildings, you might be wondering how to define an accurate baseline for each one. A baseline helps you track energy use and set goals for reducing consumption. But if you are still manually generating baselines for each building, it can be a time-consuming and error-prone process. This post, aim to exemplified why it is important to automatically generate baselines for buildings to start saving energy.
Why is it important to have a Baseline Model?
A baseline model is a formula that explains a building’s consumption against which you can measure progress or results. It represents your building's energy consumption over a set period of time, usually one year. By comparing your building's real consumption to its baseline consumption, you can see how your building is performing over time. Replicate this through your portfolio and you can track the energy savings across all your organisation.
There are many reasons why it's important to have a baseline:
- Baseline models help you track progress toward energy reduction goals. If you are trying to reduce your energy use by 10% over the next year, having a baseline will allow you to see if you're on track to reach that goal.
- Baseline models can take into account the context variables of your building that can influence energy consumption such as external temperature, degree days data, occupancy, and production. Using these variables in the model will augment its accuracy compared to using the previous year's consumption.
- Baseline models can adapt to the situation of your building: if the normal operation of your building is altered in any way (after-hours event, maintenance works…) that can influence energy consumption, your baseline can reflect this so that you can still track your savings accurately. There are many other reasons we could think of, but these are just a few of the most important ones. In short, having a baseline is essential for any serious effort to improve energy efficiency.
What does it take to create a good Baseline Consumption Model?
You will need at least one year of historical data to take into account seasonality for the building consumption and for any variable that might influence it such as temperature, degree days, occupancy, and production.
The most important variables are:
- Temperature: The heating (or cooling) demand is strongly influenced by the ambient temperature. For example, if it is cold outside, more energy will be required for heating purposes; conversely, if it's hot outside more energy will be required for cooling purposes. The weather forecast can give you an indication of how much heating/cooling demand may occur during different seasons or weather conditions.
- Degree Days: Degree Days are defined as the number of degrees Celsius above or below a fixed base temperature. They indicate how much heating or cooling is needed over time in order to reach thermal comfort inside buildings. They are automatically calculated in Dexma.
Why you should automatically generate Baselines for your entire Building Portfolio
Traditionally a baseline is calculated using a spreadsheet and or other specialised statistical tools, to perform multiple linear regression calculations. However, using this method, it can take you hours to obtain a valid baseline model for a single building. Using a Baseline Generator, you can obtain a baseline formula and create a Measure & Verification to compare that baseline consumption with your building's real consumption.
How to Automatically generate Baselines for your entire Building Portfolio
In order to automatically generate a baseline, you will first need to gather data on your building's energy use. This data can come from a variety of sources, including utility bills, fiscal metres, IoT devices and sub-metres. Once you have this data, you will need to feed it into an energy management software which can process data from all these sources automatically. Once you have your data, you can run the Baseline Generator to start generating baseline models and their linked measure and verification project with a few clicks. By selecting the energy source, periods, and reference device type, you can start generating baselines for each building. The baselines will be created using energy consumption data as well as degree days or temperature data linked to each building.
Tracking Energy Savings with the generated Baseline
Once the baseline models are calculated you can use an energy management software with a measure and verification module in order to track your savings.