Translation of "쓸모없는" in English

마치 쓸모없는 것처럼요.

As if they were not good enough.

그렇다면 이런 에너지를 얻을수 있을까요 아니면 그냥 쓸모없는 일일까요?

Now can we harvest some of this energy, or is it just totally useless?