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REopt Lite Tutorial: Resilience Inputs (Text Version)

This is a text version of the video REopt Lite Tutorial: Resilience Inputs.

If you select resilience as your focus, there are a few extra inputs required. The first is critical load. This is the load that must be met during the grid outage that you specify.

The critical load can be entered in three ways.

The easiest way is to specify the critical load as a percentage. It can be higher or lower than the typical load, depending on the use of the building during a grid outage. To help estimate this number, consider factors such as: Does my whole building need power during an outage, or just portions? The percentage of critical load has a big impact on the outputs. Because it can be difficult to get an accurate estimate, you might want to try different levels of critical load—for example, 50%, 75%, and 100%.

The most accurate way to enter the critical load is to upload it. This data may be available to you if there are submeters on individual buildings that are part of the critical infrastructure, or if a building has a critical load panel that is metered.

Finally, you can build your own critical load profile from common load components. You must be logged in to do so. Through the build process, you can add load types, such as A/C units, lighting, or printers. The Power, Quantity, Start Hour, End Hour, Start Month, and End Month are all prepopulated by defaults, but can be adjusted. Once you save the critical load profile, it will be available for future analyses when you are logged in to REopt Lite®.

You will need to provide some information about the outage you want to model. The outage duration is specified in hours. For reference, 1 week is 168 hours. You can select the outage start date from the calendar, and the outage start time from the dropdown.

You can also autoselect the outage start date based on your load profile. By clicking “start outage on peak,” the maximum power requirement of your critical load will be included in the outage. This is a good way to plan for a worst-case scenario.

You can also specify if this is an outage that occurs annually, or once per project lifetime. Your selection here will not impact the system sizes, just financial results.

Finally, you can also evaluate the economics of adding a backup generator to meet the critical load during an outage. The generator won’t run while the grid is operating.

REopt Lite will size the generator for you. In this case, the model considers the costs and benefits of the generator, alongside the other technologies evaluated, to meet the outage at the lowest life cycle cost of energy.

You can also specify an existing generator. In this case, the existing generator size will be the minimum size used in the optimization, but REopt Lite may still choose to add additional generator capacity.

There won’t be any installation costs for the existing generator, but the fuel costs will still apply. The default assumptions are for a diesel generator, but can be changed to reflect a natural gas option.