Charge the electric vehicle at night and sell the electricity during the day. Can EV owners really make money from charging?
New energy vehicle owners probably never thought that after enjoying various benefits such as cheap charging, exemption from purchase tax, and no traffic restrictions, they can even sell the electricity charged in their cars to make money.
Just recently, the term V2G, which seems to have been rarely mentioned, has become active again.
In the middle of this month, Tianjin announced that it will launch a "Vehicle-Grid Interaction Demonstration Month" in September and October, aiming to explore new forms of V2G. Two days later, Guangzhou also issued the "Work Plan for Guangzhou to Build a National Pilot City for Large-scale Application of Vehicle-Grid Interaction", stating that it will promote the large-scale application of V2G.
Coincidentally, at almost the same time, BMW announced in Germany that it will launch Germany's first V2G program for vehicle owners together with a company named E.ON, and the newly released BMW iX3 will support it.
It feels like a V2G wave has swept across both at home and abroad.
If you haven't heard of V2G before, it's very easy to understand. It's actually an abbreviation for Vehicle to Grid, which refers to the function of new energy vehicles sending electricity back to the power grid.
With this function, new energy vehicle owners can make money by buying low and selling high and reselling electricity.
As we all know, whether it's commercial or residential electricity, the electricity fees charged by the power grid are divided into more expensive peak electricity and cheaper off-peak electricity according to different times. The price difference between the two can sometimes reach one or even several times.
So, just like a supermarket buying and selling goods, as long as new energy vehicle owners charge their cars when the electricity price is low and then sell the electricity back to the power grid through V2G when the price is high, they can earn the price difference.
Moreover, they can earn quite a lot.
Take the V2G pilot projects in Guangzhou and Shenzhen in April this year as an example. The off-peak residential electricity price in Shenzhen is 0.4 yuan per kilowatt-hour, while the highest price the power grid pays for the electricity from people's cars is close to 1 yuan per kilowatt-hour. Coupled with the subsidies from the power grid for the pilot project, vehicle owners can get 4 yuan from the power grid for each kilowatt-hour of electricity sold, making a profit of 3.6 yuan directly.
As long as the discharge power is high enough, the money will keep coming in. Look at this blogger on Xiaohongshu. They earned 120 yuan in just half an hour of discharging, with a profit margin and earning speed comparable to XX.
Even in the cooperation between BMW and E.ON mentioned earlier, it is stated that vehicle owners can earn a certain amount of money each year (720 euros, approximately 6002 yuan), which is used to increase the attractiveness.
So, isn't this a complete loss-making deal for the power grid? Why does it encourage and even pay subsidies for people to sell electricity?
This has to do with the potential "peak shaving and valley filling" effect behind the V2G function.
You know, although China's power grid infrastructure is already the best in the world, it still has some difficulties in dealing with the national electricity consumption peak.
For example, during the peak electricity consumption in the summer of 2023, the maximum national electricity load reached 1.37 billion kilowatts, while the total power generation capacity of all domestic power generation methods is only 2.6 billion kilowatts, and 40% of it comes from wind and photovoltaic power generation, which have relatively unstable power generation.
Therefore, during the peak electricity consumption, the power grid either has to generate electricity crazily or implement power rationing, which affects people's daily lives. It's really under a lot of pressure.
However, in contrast to the peak, when people use little electricity, such as in the early morning, although the national electricity consumption is low, power generation methods like dams are still working. The generated electricity is wasted because no one uses it.
Looking at the numerous new energy vehicles on the street, they are perfect for storing the wasted electricity and relieving the power grid's pressure during peak hours, that is, peak shaving and valley filling.
After all, the number of new energy vehicles in China has exceeded 36 million. Theoretically, if each vehicle has an external discharge capacity of 10kW, the total power supply capacity will be close to 400 million kilowatts, which is about one-third of the national peak load.
This is not just an electric vehicle; it's a distributed power grid!
If these vehicles can be utilized during peak electricity consumption, it can not only greatly relieve the power grid's pressure but also encourage people to charge their cars during off-peak hours at night and sell the originally wasted electricity. It's really a win-win situation.
This is why the V2G field has become lively again after several years of silence. The growth rate of new energy vehicles in China has been extremely fast in the past one or two years. Originally, "peak shaving and valley filling" was just a theoretical concept.
Now, after serious research, it seems that it can really be achieved!
I know that after reading this, some brothers may have started looking for places nearby where they can make money through V2G and are ready to sell electricity to the national power grid until it goes bankrupt.
But after opening the charging pile map, you guys should have also found that although the ideal is beautiful, the reality is cruel.
The number of charging piles around us that support the electricity-selling function is actually very small. In most cities, even in many first-tier cities, there isn't even one charging pile that supports V2G.
Why is this? Didn't they say that V2G is great?
Actually, just like the slow rollout of ultra-fast charging piles back then, there are many obstacles and challenges behind the popularization of V2G technology. For the time being, it may be difficult for us to get rich by reselling electricity.
There are reasons related to the vehicles, the charging piles, and of course, the power grid. In summary, it's both expensive and difficult.
From the perspective of new energy vehicles, if a vehicle wants to sell electricity to the power grid, it must be equipped with an on-board charger (OBC) that supports bidirectional input and have a relatively high-power external discharge capacity.
However, the cost of a bidirectional OBC is 20 - 30% higher than that of a unidirectional one, which means an additional cost of about a thousand yuan. Not all car manufacturers are willing to use it.
Even if a bidirectional OBC is used, it's very difficult to unify the bidirectional charging protocols.
Currently, there is only a recommended standard (GB/T 20234) for vehicle charging interfaces in China. As a result, the charging protocols between car manufacturers and charging pile companies are very diverse. It's not as simple as just finding a V2G charging pile and plugging in the vehicle to start charging.
The way to solve this problem is very primitive and not very efficient, which is through cooperation between enterprises.
For example, in order to promote V2G, NIO signed agreements with China Southern Power Grid and had cooperation talks with CATL. Only then could vehicle owners participate in the small-scale pilot project.
It'll probably take some time before the protocols between car manufacturers, the power grid, and charging piles can be fully integrated.
Of course, the cost and protocol issues are relatively easy to solve. I think the real challenge that takes time and effort is how to make V2G truly effective on the power grid side.
Although as mentioned earlier, V2G can achieve the effect of peak shaving and valley filling, there is a cost.
For example, if many vehicles sell electricity to the power grid at the same time, it may inject a lot of harmonics into the distribution network and cause an instantaneous increase in the voltage of the distribution network.
On the one hand, this may increase the wear and tear of power grid equipment such as transformers and reduce their service life. On the other hand, many of the short-circuit protection mechanisms of traditional power grid facilities are still based on the previous one-way power transmission.
If not handled properly during large-scale V2G implementation, when a short-circuit problem occurs, it may be difficult to locate and isolate the fault point. In severe cases, it may lead to large-scale power outages.
Therefore, in order to adapt to the large-scale promotion of V2G, the distribution network also needs to undergo corresponding large-scale upgrades. For example, using better inverters, smarter dispatching systems, and even upgrading the regional distribution network. Both the engineering and technical difficulties are quite significant.
This is why the V2G tests in the cities mentioned at the beginning are all small-scale and short-term pilot projects. For the distribution network, this is almost like a stress test.
In addition, just like the ultra-fast charging piles back then, the cost of charging piles that support the V2G function is 2 - 3 times that of ordinary fast charging piles. It's really too expensive. As a result, popularizing V2G charging has become a systematic project that requires car manufacturers to adapt, the power grid to upgrade, and the charging infrastructure to be greatly updated.
Of course, as a country known for its infrastructure construction, we always take on difficult tasks.
As of August this year, a total of 13 provinces and municipalities have introduced policies and subsidies related to V2G, covering everything from private cars, online car-hailing vehicles to commercial vehicles like heavy trucks. It seems that there is a strong momentum to turn V2G into a national project.
So, I estimate that there will be more small-scale pilot projects like the ones mentioned at the beginning in the future, and they will last longer and cover more cities.
It's time for NIO and Tesla owners who are enjoying lifetime wireless charging and battery swapping to take action.
Image and data sources
China Southern Power Grid Energy Storage Technology signs an agreement with NIO Energy | NIO
BMW launches Germany's first personal commercial V2G program, with users earning up to 720 euros per year
Is The Vehicle To Grid Technology The Future Of Electric Car | ENGIE Research & Innovation
Fiat to launch a V2G test project for 600 - 7