The pilot project for market-oriented trading of 12 MW distributed power generation in Suzhou Industrial Park has recently been officially put into operation. It is jointly invested by Prolos Group, enterprises under the Chinese consortium, and Suzhou Logistics Center. It is the first "one to many" distributed photovoltaic power generation market-oriented trading pilot project in China, which has reference significance for further promoting market-oriented electricity trading. The market-oriented trading of distributed power generation, commonly known as "selling electricity through walls," has been piloted in various regions for several years and is still lukewarm to this day. What are the obstacles to promoting "wall to wall electricity sales" on a large scale, and what are the ways to open up breakthroughs? Realize the nearby consumption of green electricity and come to Suzhou Industrial Park. The reporter saw in Suzhou Prolos Logistics Park and Suzhou Logistics Center that the warehouse roof has become a natural photovoltaic power generation site. The relevant person in charge introduced that these roofs are covered with approximately 200000 square meters of photovoltaic panels, with an installed capacity of about 12 megawatts. It is expected that the annual power generation will be 12.23 million kilowatt hours, which is equivalent to reducing nearly 9000 tons of carbon dioxide emissions annually. In the past, these green electricity could be sold to the power grid on the basis of meeting the self use needs of power generation enterprises. Now, there is no need to sacrifice proximity for distance. Power generation companies can directly sell it to electricity consuming companies within the same 110 kV substation, achieving nearby consumption. Professor Gao Ciwei from Southeast University introduced that unlike the two common business models in the industry, "spontaneous self use, surplus electricity grid connection" and "full grid connection", the "wall to wall electricity sales" project introduces third-party transactions at the settlement level, and directly settles with users through local power trading centers. The person in charge of relevant departments in Suzhou Industrial Park stated that there is a situation in Suzhou where the roof area is large but the electricity consumption is small, and the surrounding energy demand is strong. In this situation, "full internet access" does not have investment value, and "self use" does not have access conditions. "Wall to wall electricity sales" can effectively solve such problems. The fact that pilot projects have been implemented one after another is that "selling electricity through walls" is not a new thing. In 2017, the National Development and Reform Commission and the National Energy Administration issued the "Notice on Launching Pilot Projects for Marketization of Distributed Power Generation Trading" (hereinafter referred to as the "Notice"), supporting regions with good resource conditions, high electricity demand, and good grid access conditions to participate in the construction of trading pilot projects. At the end of 2019, the Jiangsu Regulatory Office of the National Energy Administration and the Jiangsu Provincial Development and Reform Commission jointly issued the "Jiangsu Province Distributed Power Generation Marketization Trading Rules (Trial)", which clarified the registration, subject, and transaction details of distributed power generation projects participating in market-oriented trading. This is the first province in China to issue the implementation rules for relevant pilot projects. On December 31, 2020, the pilot project for market-oriented trading of 5 MW distributed power generation in Zhenglu Industrial Park, Tianning District, Changzhou City, Jiangsu Province was successfully connected to the grid for power generation. It is the first successful pilot project for market-oriented trading of distributed power generation in China, adopting the "agricultural photovoltaic complementary" model. The annual power generation is 6.8 million kilowatt hours, and the generated power is directly traded in the market within the power supply area of the 110 kV Wucheng substation. At this point, the pilot program for market-oriented trading of distributed power generation in Jiangsu Province has officially begun. In 2021, Shandong Province and Zhejiang Province also issued documents encouraging the local development and utilization of distributed renewable energy electricity, and conducting market-oriented transactions. In foreign countries, there have also been successful cases of "wall to wall electricity sales", such as Rotterdam Port in the Netherlands, which launched the electricity trading platform Distro in August 2020 with blockchain+artificial intelligence technology support. Within two months of its launch, the platform completed 20 million transactions, of which 92% of solar power was produced and sold immediately, building a peer-to-peer trading bridge between photovoltaic owners, public institutions, and corporate buyers. According to statistics from S&P Global Platts, after the trial operation of the Distro platform, energy costs for end-users decreased by 11%, while revenue for renewable energy producers increased by 14%; Meanwhile, the return on investment for battery energy storage has increased by 20%. The responsibilities, rights, and interests need to be further clarified. Although the "Notice" has proposed the pilot program of "selling electricity through walls" for more than 6 years, the related progress has been relatively slow. Why on earth is this? In Gao Ciwei's view, the slow implementation of "wall to wall electricity sales" is mainly due to the lack of a sound electricity pricing mechanism. The Notice stipulates that power grid companies may charge "grid fees" for distributed new energy projects. But this "grid fee" minus cross subsidies, government funds, and surcharges in the transmission and distribution electricity price may only charge a fee of 0.015-0.05 yuan per kilowatt hour. If under the same voltage level, the "overhead fee" may even be zero. Prior to this, the "grid fee" and "system operation fee" charged by the power grid company were generally above 0.2 yuan/kilowatt hour. Currently, the power grid is designed according to the maximum load of all users. Although both parties in the "wall to wall electricity sales" transaction have reduced their purchases of electricity from the power grid, the electricity load of both parties still needs to be taken into consideration during the construction of the power grid, which means that the power grid enterprise will bear the guarantee of backup power supply. Gao Ciwei said that if distributed new energy adopts "wall to wall sales", the seller and buyer can certainly achieve a win-win situation, but this is a loss for the power grid company, and it comes at the cost of the entire system as a backup. If both parties involved in the transaction do not pass through the existing transmission and distribution power grid, but instead build a dedicated line, then without policy support, the economic feasibility of distributed new energy participating in market transactions is not superior. In addition, doing so will also lead to an imbalance in the current "responsibility, power, and benefit" relationship in the power grid, resulting in a decrease in the revenue from electricity sales or transmission and distribution by power grid enterprises. Therefore, Gao Ciwei believes that in order to make good use of new energy, it is necessary to further promote the reform of the power system. If we want to truly achieve a breakthrough in "wall to wall electricity sales", we need to redefine the relationship between responsibility and rights, carry out structural reforms on electricity prices, promote investment in new energy projects, and promote energy conservation and carbon reduction. The benefits of linking "wall to wall electricity sales" are many. With the increase in the installed capacity of distributed new energy projects, the problem of green electricity consumption is becoming increasingly apparent. Promoting "wall to wall electricity sales" means that the power generation of distributed new energy projects can be traded with multiple electricity users within a large range, without being limited to binding a single user, which is conducive to solving the problems faced by owners of distributed new energy projects in the "spontaneous self use" mode, such as difficulty in collecting electricity bills. Compared to fully connected projects, "wall to wall electricity sales" can provide new energy project owners with relatively higher transaction electricity prices. Industry insiders believe that "wall to wall electricity sales" will further promote the market-oriented reform of electricity, broaden the sales channels of distributed new energy projects, and improve profitability. In addition, "selling electricity through walls" also has a positive effect on power generation enterprises. "Selling electricity through walls" can increase the cash flow income of power generation enterprises, improve their competitiveness, and reduce their dependence on national electricity price subsidies. Meanwhile, the industry can form a virtuous cycle through market competition and allocation. Not only that, "selling electricity through walls" can also shorten the distance of power transmission, reduce transmission and distribution costs, and help industrial and commercial enterprises on the user side reduce overall electricity costs; In addition, consuming green electricity can not only eliminate energy consumption indicators, but also accelerate the pace of enterprises' green and low-carbon transformation and reduce carbon emissions. (Lai Xin She)