Lockdowns have been a controversial aspect of the COVID-19 pandemic. Yes, they undoubtedly save lives, but they also cause major ongoing economic issues – disrupting industries, causing job losses and associated financial pain.
新冠疫情期间的居家隔离饱受争议。毫无疑问，居家隔离能挽救生命，但也会造成重大经济问题，各行各业停摆，造成失业和相关经济损失。
But another thing lockdowns have done all over the world is decrease air pollution, and new research shows an interesting flow-on effect of this.
但居家隔离也有好处，全球的空气污染减少了，新的研究展示了这一现象的有趣影响。
The new study has looked at solar power in Delhi – one of the most polluted cities in the world – and has found that the reduction in air pollution has allowed significantly more sunlight to get through to solar panels in the city, increasing their output.
这项新研究观察了德里的太阳能，德里是全球污染最严重的城市之一。研究发现空气污染的减少大大增加了该市照射在太阳能电池板上的阳光，提高了电量输出。
"The increase that we saw is equivalent to the difference between what a photovoltaic (PV) installation in Houston would produce compared with one in Toronto," says first author Ian Marius Peters of Helmholtz-Institut Erlangen-Nürnberg for Renewable Energies in Germany.
德国赫尔姆霍兹爱尔兰根纽伦堡可再生能源研究所第一作者Ian Marius Peters说：“我们发现发电量增加前后的差别相当于休斯顿光伏设施的发电量和多伦多之间的差别。”
"I expected to see some difference, but I was surprised by how clearly the effect was visible."
“我之前预料到会有些区别，但效果太过明显，令我惊讶。”
Delhi went into a strict lockdown on the 24 March 2020. The team looked at the PM2.5 particle concentration, a measure of fine particles less than 2.5 micrometres in diameter, in the air at the US embassy in Delhi before and after the lockdown – and compared them to the last few years at the same time of the year.
从2020年3月份开始德里严格执行居家隔离，研究团队监测了隔离前后位于德里的美国大使馆内空气中的PM2.5浓度，也就是直径小于2.5微米的微粒，并与前几年的同期做了对比。
They also looked at the clear sky irradiance – which is how much sunlight reaches Earth's surface without being scattered or absorbed by particles and gases in the air.
他们也观察了晴空辐照度，即到达地球表面，在空中没有被散射或被微粒和气体吸收的阳光照射量。
The team found that, overall, the amount of sunlight reaching solar panels in Delhi increased by around 8 percent in late March 2020, and 6 percent in April 2020 compared to similar dates in earlier years.
研究团队发现，总体来看，与前几年的同期相比，在德里到达太阳能电池板上的阳光照射量在2020年3月末增加了8%左右，在2020年4月份增加了6%。