How much does it cost to make a Solar EV charging station?

 Introduction: We have heard a lot about the environmental pollution, climate change and global warming. In different parts of the world scientists, researchers and innovators are struggling to find a solution for the ever worsening situation of our environment. One such innovation was promoting the use of Electric Vehicles and reducing the emissions from the traditional engine based cars by replacing them with the EVs. There has been a tremendous progress in the field and today we have EVs which are better than traditional engine based vehicles. We are seeing cars which are both powerful and provide a range of about 400km per full charge. Though the prices somewhat are higher but on a longer term the investment is recovered by saving fuel prices. In India where on average you pay 90-100 Rs for engine cars to get 10Kwh of energy, for EVs the price is about 50-55 Rs for the same 10Kwh of the energy. Hence Electric Vehicles are a better option to choose and in future will have a high demand.

Challenge: No doubt we today have manufactured EVs better than normal cars but there use is limited. The main reason behind this is the lack of infrastructure for electric vehicles. Like for engine based cars we have petrol pumps and service stations set up at every place, the charging stations for EVs and there service stations must be set up. Though EVs require much less maintenance and servicing our main focus thus remains to set up the charging stations across various places to make the EVs successful. It may seem an easy task to do but setting and maintaining the charging station requires some good investment.  Moreover, the electricity for the stations needs to be from a renewable source i.e. hydro-electricity, wind mills, solar electricity and so on.   What the main issue is that at most places in the world traditional electricity comes from fossil fuel based generators which power the cities. Purchasing electricity form these sources will not only increase the pollution but will also lead to the depletion of the resources which is exactly opposite of what electric vehicles were meant for.

Solution: Keeping in mind the latter challenges, the best solution for the problem is to build solar based charging stations. These stations will provide free renewable electricity to the station using the solar panels and thus to the cars. All we need is some efficient solar panels, BESS (Battery energy storage systems) and the charger system. In case of any power shortage which have a rare chance to occur the extra electricity can easily be purchased from the local power lines. Additionally the extra power produced can be sold to the power company through on-grid installation of the solar power system.

Solar panels to be used: I have spent a lot of time researching the best among the solar panels which can be used for our solar power system and there come out to be two possible solar panels of interest.

1.    Mono Crystalline single junction solar panel : These are the commonly used budget friendly and high efficiency solar panels providing an efficiency of about 23-25% and costing about 30 -40 Rs per watt (excluding shipping and additional charges).

2.    Multi-Junction Solar Panels: These are high efficiency high cost solar panels and will be used at places where the space available is less.  These are currently not available for commercial use and dealers are quite hard to find. Additionally industries may manufacture some panels on demand but these are hard to find. What makes it come under our interest is its high efficiency of about 35-45% that can save a lot of space and work well under dim lighting conditions too.

BESS: Battery Energy Storage System is an important part of the project as the energy produced by the solar panels must be stored before use. This is where a BESS comes into play. This is not something big but a system of Batteries and charge controllers to ensure the storage of electric energy and its regulation. Based on the demand and the availability of space we can decide the correct BESS for our project.

Chargers: It is important that a charging station should have fast chargers and that too adaptable with all kind of sockets. Below table shows the list of most commonly used charger sockets.

EV charger specifications

Model	Battery type	Charger	Adapter	Capacity( kW h)
Renault Fluence Z.E.	lithium-ion	3.5kW AC onboard charger Optional Zoe's Chameleon charger (43 kW)	10A 220V-240V household charger; SAE J1772	22
Tesla Model S P90D	lithium-ion	11 kW AC onboard charger 120 kW DC fast charger	SAE J1772 public chargers. Adapters to IEC 60309 5 PIN Red 16A/3- phase (400 V) or IEC 60309 3 PIN Blue 32A/single-phase (240 V) or some other kinds of domestic adapter or general adapters	90
Toyota Prius Plug-in Hybrid	lithium-ion	3.3kW AC onboard charger	120v household outlet; SAE J1772	9
BMW i3	lithium-ion	7.4kW AC onboard charger DC fast charger	SAE J1772 Optional Combo DC)	22
Mitsubishi i-MiEV	lithium-ion	3.3kW AC onboard charger 44kW DC fast charger	adapters for domestic AC sockets (110-240 V); 15 A 240 V AC (3.6 kW) on the SAE J1772-2009 inlet, optional Chademo (max 44 kW 480 V DC[3]);	16
Nissan Leaf	lithium-ion	6.6kW AC on board charger DC fast charger	SAE J1772 CHAdeMO	27
Ford Focus Electric	lithium-ion	6.6kW AC onboard charger	120V convenienc e charge cord 240V Home Charging Station  SAE-J1772	23

*research papers of Department of Electrical Engineering Blekinge Institute of Technology Karlskrona Sweden 2016

DC Chargers: This type of a charger is installed in a power station for quick charging of vehicles there are a few notable technologies available and these are also continuously under development. All DC chargers must be able to do these main things:

Transfer charge

Exchange data

Earth shorts and leaks

A charging station must have a good variety of connectors most important of them are listed:

Charger	Voltages (V)	Power (KW)	Current (Amps)
CSS	200-1000	350	350
CHAdeMO	50-500	200	400
Tesla Super chargers	400-500	120	250
GB/T	750-1000		250

 *source: TUDelft

AC chargers: Some vehicles have an onboard charger which converts AC electricity to DC electricity for charging the battery. AC connectors are equally important as DC connectors though these perform charging slower, it costs little less and can be used to charge vehicles parked for longer time for example near offices.

Charger	Voltages (V)	Power (KW)	Current (Amps)
SAEJ1772	120-240	1.44	80
SAEJ1772 TYPE2 1PHASE	130	2	80
SAEJ1772 TYPE2 3PHASE	400	20	63
Tesla	240	17	20

 *source TUDelft

 

Charge Controllers: MPPT controlers are best charge controlers for the project as they are effecient and enduring. Though the cost might be high. If the budget is less the using series controllers will reduce much of the cost.

 

Estimates: Below are some rough estimate for the project. All other charges such as taxes labour and maintenance and not included in the table.

Investments per station:

Unit Type	Power Requirement per day (Kwh)	Solar Panels (Kw / INR)	BESS (Battery / INR)	Chargers (No.s / INR)	Total (INR)
Small (5+ EVs per day)	150	30 / 10,00,000	Lead Acid / 10Lakhs	1 DC + 1 AC / 10Lakhs	30Lakhs +Additional
Medium (10+ EVs per day)	400	80 / 30,00,000	Li-ion/ 15-20Lakhs (*imported)	2 DC + 1 AC / 15Lakhs	65Lakhs +Additional
Large (20+ EVs per day)	1000	200 / 70,00,000	Li-ion/ 45-50Lakhs (*imported)	5 DC+  3 AC/ 40Lakhs	1.6Crores +Additional

*Approximately calculated

 

Profit per month per station:

Unit Type	Energy Produced (Kwh)	Avg.Cost Per Unit (INR)	Cost per unit DC fast charging		Cost per unit for AC charging	Apprx.Total Sale (INR)	Recovery term
Small (5+ EVs per day)	4,500+	15.00		20.00	5.00	70,000	4 years
Medium (10+ EVs per day)	12,000+	15.00		20.00	5.00	2,00,000	3years 6 months
Large (20+ EVs per day)	30,000+	15.00		20.00	5.00	5,00,000	3 years

 

For more refferences on the components please consider visitng this page:

https://www.newinnovations.tech/2021/12/solar-based-charging-station.html?m=1