Remarkably, the growth in the market could have been even larger, if it were not for a severe shortage of batteries limiting the possibility to meet customer demand and causing, months-long, lengthy delays to install R-BESS products. This issue was particularly felt in less developed markets, where the sudden spike in demand caught distributors by surprise as they struggled to find products for their clients. Even mature R-BESS markets have been suffering from a lack of batteries, which continue to be the missing product link for solar system technology after modules shortages have been solved and inverter shortages are being addressed.  Over the last years, the continent relied on a handful of R-BESS pioneers, primarily Europe’s largest solar market Germany, which is also the country with the largest R-BESS installed residential battery storage volume by far. In Germany, home storage started first gaining traction after it switched from a full Feed-in Tariff (FIT) scheme to a model supporting self consumption, in combination with a premium for excess power, and backed by an attractive R-BESS subsidy programme of its development bank KfW that was slowly phased out. Later, home battery markets started to emerge as well in a few other countries – Italy, the United Kingdom, and Austria – while hardly any capacity was installed in the rest of Europe. Today, R-BESS technology applications can be seen in a quickly growing number of European countries, and, as volatile energy prices reaching unknown heights are severely affecting households across the whole continent, the home storage business case is becoming appealing in many different European regions. For the second year in a row, the home storage growth path in Europe turned out to be significantly higher than what we had previously forecasted. In last year’s edition of this report, we assumed the market would grow 28% to 1.4 GWh. The positive evolution of the market conditions exceeded even our most optimistic expectations: our High Scenario anticipated 1.8 GWh of annually installed capacity; actual installations were 27% higher. The exceptional increase in the annual market is well reflected in the growth of the total operating home storage capacity. The residential BESS fleet jumped from just over 3.1 GWh in 2020 to 5.4 GWh in 2021, with a 74% year-on-year increase. Unlike last year, the annual market growth rate is higher than the growth rate in cumulative capacity, a sign that the total operating fleet has reached substantial volumes and the technology is entering a new deployment phase. Total R-BESS capacity has grown 13 times its size, compared to just five years ago.