Using alternative fuels and improving energy efficiency is thus both an ecological necessity and a technological challenge.

因此，使用替代燃料和提高能源效率既是生态需要，也是技术挑战。

youdao

A Lot of Scope Seen for Improving Energy efficiency.

在提高能源使用效率方面还有很大潜力。

youdao

The biggest chunk, around a quarter, is going on improving energy efficiency.

其中最大的一笔开销，其四分之一的金额将用于提高能源利用率。

youdao

On the plus side, the foundation acknowledged that substantial progress had been made in improving energy efficiency in both new and existing homes and reducing fuel poverty among vulnerable groups.

BBC: NEWS | Business | Homebuyers 'face growing worries'

Yet, despite the real energy cost savings and environmental benefits associated with improving home energy efficiency, a series of barriers have prevented a self-sustaining retrofit market from forming.

WHITEHOUSE: THE WHITE HOUSE

My recommendation is to spend half your money improving the energy efficiency of your house.

FORBES: With $2,000 To Spend, What's The Most Effective Way To Reduce One's Carbon Footprint?