Hi all,

We submitted a CIR for Renewable Energy Production credit. However, from the ruling below, I feel that I should post it in Optimize Energy Performance. Can anyone help me clarify how to claim the savings associated with using the heat rejection from the LNG plant? From the modelling method that I proposed, does this mean I need to model purchased chilled water for both baseline and proposed cases and then deduct chilled water supplied by the LNG plant from the proposed case without claiming it as renewable energy? Additionally, since it is not renewable energy, can I claim saving for the prerequisite, Minimum Energy Performance? Thank you.

Request 

Our project is a 3-story office building located on a Liquified Natural Gas (LNG) Terminal and production plant near the Gulf of Thailand (Climate Zone 1A per ASHRAE 90.1-2010). Due to the process of vaporization of LNG to natural gas, water is fed into the plant and therefore, a large amount of chilled water at 5 C is generated as by-product. Normally this chilled water is discharged to the sea, however, our project aims to recover that chilled water to be used for the cooling of the building. The design team is planning to pump this chilled water to the building’s air handling units in order to cool the interior spaces.

The project proposes to claim this by-product chilled water as a renewable energy source since it is a waste from a gas production process that otherwise be drained to the sea. In the energy simulation, we will model both Baseline and Proposed cases to utilize purchased chilled water according to ASHRAE 90.1-2010 Section G3.1.1.2 and use the same chilled water cost rate. The energy models’ scope will account for downstream equipment such as pumps. The amount of cooling energy supplied by the chilled water from the gas production plant will be used to claim a percentage of energy offset by the renewable energy source.

Ruling

The project is requesting that waste chilled water, a byproduct of LNG vaporization process, be counted as a renewable energy source for this project. No, this waste chilled water does not qualify as a renewable energy source since its availability is dependent on the amount of LNG processed and natural gas is not a renewable energy source.

However, it does seem reasonable for the project to claim the savings associated with using the heat rejection from the LNG plant and modelling the baseline and Proposed case using the methodology for district cooling systems and the default chilled water energy rate appears to be reasonable. Ensure that the pumping energy from any downstream equipment is included in the Baseline and Proposed case energy consumption and costs.