Strategic Decarbonization Assessment (SDA)

On the “Building info and assumptions” tab, users input basic information about the building: floor areas, space types, fuel types and consumption (bill) data. 

The “Building info and assumptions” tab enables users to communicate building information in a highly customized way at a very granular level. It is doubtful that most EBC users will need to take full advantage of all the functionality to develop a competitive EBC proposal.  You do not need to change the default values unless your business case is materially impacted by these estimates (i.e., you are trying to reduce maintenance costs in addition to energy costs). Most of these assumptions are found in the “Real Estate Characteristics” drop down. Very few EBC users have needed these features, so we suggest you use the defaults, even though they were based on pre-pandemic New York data. Note that all red/orange cells are optional, but not all blue cells are required as many include default values.

This drop down is where you can change the default escalations rates for general costs and specific fuel costs over time. Sensitivity analyses that explore a variety of future rate scenarios are encouraged to show that you have considered the sensitivity/fragility/resilience of your plan in a variety of futures. 

The “Regulatory Assumptions” drop down on this tab includes NYSERDA default values for fuel specific emissions factors stipulated by LL97. This section also automatically calculates the building’s LL97 emissions limits for the 2024-2029 and 2030-2034 time periods using building typology and GSF inputs on the same tab.*

*Note, we have not updated the tool to reflect the proposed changes to LL97 building classes and emissions factors. We do not expect this to impact most EBC proposals, but please let us know if your proposal is impacted in some way.

On the “Equipment Inventory” tab, users will input major energy using equipment. All the fossil fuel equipment and at least 80% of total energy using equipment should be inventoried and reported on this tab. Very similar or identical equipment can be grouped into one row (e.g. multiple AHUs of generally the same size and age). The date of installation is required as it determines the equipment life and is used to define the Business As Usual (BAU) trajectory - existing equipment is projected to continue functioning until it reaches End of Useful Life and is replaced, like for like, at that time. User-input costs for the like for like replacement are also required inputs to complete the BAU trajectory. Please note, the estimated replacement cost and year installed are required inputs for the SDA graphics. Replacement costs for decarbonization measures and BAU equipment replacement need not be overly precise - these cost numbers should be realistic to ensure ROI and NPV calculations are sufficient for comparative purposes.

NPV and savings calculations in the SDA are significantly influenced by major energy using equipment. To streamline SDA development and simplify analysis, project teams should focus on major equipment and group minor equipment together by age, if feasible. If you are not using the landlord/tenant cost/benefit breakout, keep all equipment in column I (Tenants Own/Operate) marked “No”. This tab also enables a simple summer/winter peak/off peak calculator for demand ECMs, but using this feature is optional and is not a replacement for a full 8760 hour model. 

The “Percent energy/carbon by equipment RUL” graphics to the right (cell AY) should populate as expected if everything is input correctly. This visual is often used in business case narratives, but does not appear on the Summary tab.

On the “Narrative & Measures” tab, users narratively define their alternatives and input all the ECMs (costs and energy/carbon impacts) that will be assigned to years on the “Alternatives” tab. The SDA automatically generates two BAU cases: one in which LL97 compliance is not sought and fines are applied, and one in which LL97 compliance is achieved through carbon offsets alone.

Note the measure life column is a critical input as it determines how long the measure’s savings will persist - if the measure ends without replacement you will see the corresponding uptick in energy/carbon on that year in the trajectory graphs. 

Many EBC participants are using detailed energy models and bringing the outputs from those models into the SDA. These users may streamline ECMs to minimize data entry and rely on the narrative explanation of the measures. The simplest ECM list in this case may be “Year 1 ECMs”, “Year 2 ECMs”, etc with corresponding costs and benefits; but be advised that users must explain their measures very clearly where they have aggregated costs and benefits.

On the “Alternatives” tab, users schedule ECMs and review the bar charts and trajectories between those Alternatives. The charts on this tab should illustrate the EBC business case consistent with the narrative submission. As stated before, the landlord vs. tenant breakdown for ECMs is not required (column H of Alternatives) and the subsequent charts can be disregarded if not used. 

Note the Holding period and Analysis periods can be varied independently, but most EBC users keep both set for 20 years for EBC submission.

The “Total Relative NPV Compared to Baseline - Varying Time Horizons” chart (cell AZ) is very commonly used in internal business cases to evaluate cost-effectiveness of the Alternatives over different time horizons, but it is not included on the Summary tab.

Most of the calculations happen on the “Operating Statements” tab, where an annual operating statement is created for each alternative/baseline for the 20 year analysis period. Users can review these statements as needed; however, it is not recommended to edit this portion of the tool directly. This is typically done when troubleshooting a trajectory chart that does not match user expectations.