guestrooms keycard: power adjustment for automatic lighting ctrl

You can do better than that - see Appendix D4 in the Advanced Energy Modeling Guide for LEED for a description of a methodology to claim 45% savings.

Hi Marcus,

I've already read Appendix D4 in the Advanced Energy Modeling Guide for LEED. So you think that when using a keycard system in hotel room (controlling lighting system), LEED accepts 45% savings on working hours of the lighting system?

Does the keycard system need to have any specific requirements, or a typical one can be installed?

Regards,

Yes LEED will accept the savings generated by that appendix. I am not aware of any special requirements for the system. As long as you can demonstrate that it will turn off the lights when the space is unoccupied you can claim the savings. 

Thanks you Marcus!

Finally, can you please confirm that these savings can also be claimed in LEED v4?

Best regards,

So how would you evaluate that question yourself? What could have changed?

After some research, I believe these savings can no longer be claimed in LEED v4 at least for bathroom areas (please see section 9.4.1.6 c from ASHRAE 90.1-2010). Do you agree?

Section 9.4.1.6c requires the lighting controls for the entire room that were previously allowed to be used to claim savings. Now that they are a mandatory provision you cannot claim savings since the baseline is required to have these controls.

Hi Marcus,

The building's key-card system functions in the following manner: when the card is removed (unnoccupied hours), the room's lighting and HVAC systems shut down.

We've already agreed that the project may claim credit in the lighting system. Can we claim any savings in the HVAC system?

Assuming that there is no mandatory provision for HVAC control it should be eligible for claiming savings.

Thanks Marcus.

To model these savings, I am considering a setback temperature for unnoccupied hours in the guestrooms. In order to maintain the same criteria as the lighting control (reduce by 50% the lighting power during unoccupied hours), I am considering claiming only half the savings (example: total hvac consumption with HVAC 100% on: 100 MWh; total HVAC consumption with setback: 50 MWh; reported HVAC consumption: 75 MWh). Note that the ventilation would be always ON (3 x 100% DOAs that serve all guestrooms)

Would this be an acceptable aproach?

I don't think it would be acceptable.

This is a simple matter of modifying the schedules and temperature setting. The schedule should be based on the typical occupancy levels of the hotel. The model should then determine what the savings would be. I would expect the savings to be way less than 50% and it sounds like you do too. I would also expect the savings to be way less than even 25%. If your model is showing this level of savings then I think there is something wrong with how you are modeling it.

This should be an exceptional calculation. You will need to justify the baseline and the schedules you are using to model the savings.