Solar Panel Companies
We reviewed and rated 16 companies making solar panels and/or photovoltaic (PV) systems.
There are big ethical differences between the brands.
One company scores 0/20 points, and several others languishing near the bottom of our score table.
How do solar panel brands score for carbon emissions
We assessed all companies in the guide for their carbon management and reporting. We exempted companies whose only product is solar panels from many of our usual carbon rating requirements because we consider them to be contributing to the climate transition. These companies all got a middle rating by default.
To achieve a best rating, they also had to have a credible and detailed discussion on how they had made emissions cuts in the past and would do so in the future.
Only Canadian Solar and LONGi did this because they had plans to move their operations fully to renewable energy in the next few years.
Companies which make other products were subject to our full carbon rating.
The only one to get a best was Panasonic. Sharp got a middle rating and Viessmann, REC Solar, and Hyundai all got worst.
How companies rate for supply chain management
Nearly 70% of the world’s solar cells and modules are made in China. Vietnam comes next with 8%.
Neither are countries renowned for their respect for workers’ rights. Despite publishing long sustainability reports, solar panel companies say little on workers’ rights and as a result all companies got a worst rating in our supply chain management category, apart from GB-Sol which received a best rating.
This is particularly concerning given the use of Uyghur forced labour (see below) and the fact that solar supply chains include large quantities of quartz – the mining of which is linked with silicosis – and which is often sourced from countries with poor workers’ rights regulation.
Tax conduct record of solar panel companies
The solar sector did not do well on our tax rating with only GB-Sol, Vikram Solar, Hyundai, and Yingli, getting best ratings – although there was little up-to-date corporate information on Yingli so this rating may not be reliable. LONGi got a middle rating and the rest got worst ratings.
It was notable that three of the Chinese solar companies: Jinko, Suntech, and JA Solar, were headquartered or had parents who were headquartered in the Cayman Islands (on our list of tax havens). Norwegian REC Solar itself got a best rating, but its parent Reliance Industries got a worst rating.
Political lobbying
LONGi, Canadian Solar, Sunpower, Panasonic, and REC Solar got worst ratings for their political activity. All lost marks for political lobbying in the US, some for donations to US political parties, and some for membership of the corporate lobby group, the World Economic Forum.
REC Solar did not engage in any lobbying itself but it lost marks through its fossil fuel-producing parent Reliance Industries which spent over half a million dollars on political lobbying in the US in 2022 and over a million in 2021.