Note 4. Inventories

Inventories as of April 30, 2018 and October 31, 2017 consisted of the following:

	April 30,		October 31,
	2018		2017
Raw materials	$	19,355	$	20,065
Work-in-process ⁽¹⁾		35,900		54,431
Inventories	$	55,255	$	74,496

(1)

Work-in-process includes the standard components of inventory used to build the typical modules or module components that are intended to be used in future power plant orders or to service our service agreements. Included in work-in-process as of April 30, 2018 and October 31, 2017 was $29.3 million and $46.3 million, respectively, of completed standard components.

Raw materials consist mainly of various nickel powders and steels, various other components used in producing cell stacks and purchased components for balance of plant. Work-in-process inventory is comprised of material, labor, and overhead costs incurred to build balance of plant components, fuel cell stacks and modules, which are subcomponents of a power plant.