Evidence is lacking on how inequality in homeowner uptake of solar panels has changed over time. This paper assesses changes in inequality over time using four Australian household surveys from 2012 to 2020. There is evidence of an intuitive transition where average uptake for homeowners with net-wealth just below the median (the fourth and fifth deciles) improved first, with subsequent gains for homeowners in the third net-wealth decile. However, there were still some significant shortfalls by 2020, especially for the first (i.e. lowest) net-wealth decile. In particular, the lowest net-wealth decile had lower uptake by 9.4 percentage points in 2012 and there was a similar gap below the highest decile of 10.6 percentage points in 2019–20. With control variables these corresponding gaps were 8.0 and 8.3 percentage points respectively. Inequality and changes have been less pronounced based on other aspects like education, income, and welfare status. A new policy implication is that Australian support should primarily target the bottom two net-wealth deciles among homeowners. Australia's experience can inform policies for other countries and clean energy technologies. The general implication is that policy approaches should be dynamic and detailed to address inequality changes over time in each context.

缺乏证据表明房主使用太阳能电池板的不平等是如何随着时间的推移发生变化的。本文评估变化使用 2012 年至 2020 年的四项澳大利亚家庭调查，随着时间的推移，不平等程度有所下降。有证据表明存在一种直觉转变，即净资产略低于中位数（第四和第五十分位数）的房主的平均接受率首先提高，随后第三个净财富十分位。然而，到 2020 年仍然存在一些重大不足，特别是对于第一个（即最低的）净财富十分位。特别是，2012 年净财富最低十分位数的吸纳率降低了 9.4 个百分点，与 2019-20 年最高十分位数 10.6 个百分点相比也存在类似差距。使用控制变量时，这些相应的差距分别为 8.0 和 8.3 个百分点。基于教育、收入和福利状况等其他方面，不平等和变化不太明显。一项新的政策含义是，澳大利亚的支持应主要针对房主中收入最低的两个十分位。澳大利亚的经验可以为其他国家和清洁能源技术的政策提供信息。一般的含义是，政策方法应该是动态的和详细的，以解决每种情况下随时间推移发生的不平等变化。