Generally treated as a non-gradable adjective; comparative and superlative forms are rarely used.
The company had a surplus inventory of products.
У компании был избыточный запас продукции.
The surplus funds were allocated to the new project.
Излишние средства были выделены на новый проект.
The surplus energy was stored for later use.
Избыточная энергия была сохранена для последующего использования.