Almost by definition, renewable energy sources have low running costs but high up-front costs.

很明显，可再生能源的运营成本很低，但是前期投入很高。

youdao

Almost by definition, renewable energy sources have low running costs but high up-front costs.

很明显，可再生能源的运营成本很低，但是前期投入很高。

youdao