(a) Definition. Phase change materials are products that are capable of absorbing and releasing large amounts of thermal energy by freezing and thawing at certain temperatures. Heat is absorbed or released when the material changes from solid to liquid and vice versa. Applications may include, but are not limited to, conditioning of buildings, medical applications, thermal energy storage, or cooling of food. Materials such as animal fats and plant oils that melt at desirable temperatures are typically used to make products in this category.

(b) Minimum biobased content. The Federal preferred procurement product must have a minimum biobased content of at least 71 percent, which shall be based on the amount of qualifying biobased carbon in the product as a percent of the total organic carbon in the finished product.

(c) Preference compliance date. No later than July 6, 2020, procuring agencies, in accordance with this part, will give a procurement preference for qualifying biobased phase change materials. By that date, Federal agencies responsible for drafting or reviewing specifications for products to be procured shall ensure that the relevant specifications require the use of biobased phase change materials.