majority of the retail market as switching rates of consumers to alternative suppliers is still limited (Energy Regulatory Office 2023).

_Full retail competition with private sector dominance:_ Many Western European countries implemented full retail competition dating back to 1999, when the **_United Kingdom_** launched its retail market. This significantly lowered the incumbent utilities’ (all now privately owned) market shares, as new suppliers entered the market, increasing the number of suppliers from 12 to now 32 (Neely 2023). However, the six largest utilities that are the former monopoly suppliers still account for about 61 percent of the retail market. The regulator, Ofgem, monitors competition through periodic assessments, and has intervened in the market at several points to introduce measures to enhance competition. Customer switching rates among retailers have increased since 2014, reaching a record high of 21 percent in 2019. The key driver of switching is savings which average £260 per year (explaining more than 80 percent of switching, according to Ofgem’s 2018 customers survey). Customer switching of retailers has declined significantly in the last 2 years (3% in 2022) according to McKinsey (2023) as the government has intervened in the market to cap retail tariffs to mitigate impact of price volatility. As a result, retailers could not compete on prices as they were capped by the regulator.

Several retailers in European countries have enhanced retail competition by utilizing technology to drive product heterogeneity and innovation. For example, Tibber is the first fully digital energy company in the world (Tibber 2024). Founded in 2016, it currently operates as a power retailer in **_Germany, Norway and Sweden_** . The company’s intelligent energy platform continuously searches for the cheapest green energy for its customers. Tibber’s customers can install a smart appliance in their home to monitor their smart home technology (such as heating systems and electric vehicles) and communicate with Tibber’s mobile app. They can use the app to automatically shift their power consumption to times of the day when prices are lower (Amazon Web Services 2021).

_Virtual community power pools and peer-to-peer retail electricity trading:_ Advances in technology are also enabling formation of localized electricity retail markets through peer-to-peer (P2P) electricity trading where community members buy or sell directly with each other without intermediation by conventional suppliers. In this system the end consumer becomes a prosumer (functioning as both producer and consumer) and exchanges excess electricity with other consumers in the community coordinated by a community manager (provider of controlling software or market platform), who can also be in charge of selling the collective surplus energy to third parties, providing residual power, and managing the balancing group. **_Netherlands_** started the world’s first P2P trading platform in 2014 allowing consumers to purchase electricity directly from independent renewable energy producers including from households with distributed generation. Germany is advancing P2P trading with some companies utilizing blockchain-based software platforms (for example, _enyway_ ) to allow consumers to directly buy electricity from local RE producers without intermediaries. Some communities in **_Germany_** have also started to form virtual electricity pools (for example, sonnenCommunity) connecting households with batteries and solar panels, allowing them to share electricity through a decentralized power community. In the US, the Brooklyn Energy Grid project consists of a microgrid energy market where community members can trade (locally 16