It takes 5 – 10 solar panels to charge a Tesla. The exact number of solar panels depends on factors like the tesla design parameters and the solar panel design overview.
From adding solar panels to an existing system to powering homes and companies, solar panel efficiency now extends to electric vehicles. Fortunately, the invention of electric vehicles has contributed to reducing our environmental carbon footprint. Interestingly, the electric car gets also benefits from solar power.
If you own a Tesla or intend to own one, you should know that there are multiple ways to charge this electric vehicle, and a solar panel system is one of those ways. A Tesla with solar panels is a much cleaner electric vehicle because Teslas are typically charged by stations run on fossil fuels.
Before we show you how to calculate how many solar panels you need to charge a Tesla, we’ll answer some important questions.
Can I Charge My Tesla With Solar Panels?
A resounding yes. You’re not just limited to a Tesla. With a solar system, you can also charge any electric car. Typically, electric vehicles juice up at charging stations that are run by fossil fuels from the grid power, but this means tons of tailpipe emissions.
On the flip side, with a solar EV charging station, these vehicles can juice up on solar power, and there will be no emissions from the exhaust pipes. This also means the electric car will have a longer lifespan.
Another advantage of charging your Tesla with solar panels is that you can still power up your electric vehicle in case of a blackout. If you don’t have a solar system, you’ll need the services of a solar installer to assess the size of the solar system (the number of solar panels) needed for the solar installation.
On the other hand, if you already had a solar system before you acquired your Tesla, the solar company will calculate how much electricity is needed for the extra load and install solar panels accordingly.
Factors to Consider Before you Charge a Tesla with a Solar Panel System
Tesla Design Parameters
The design parameters involve three things – the state of charge, the battery capacity, and the energy requirements of the electric vehicle.
The State of the Charge
This term is technical, but it simply means the limits of a Tesla battery (the upper and lower limits). Tesla cars typically have a state of charge that ranges between 20%-80%. The former is the depth discharge of a Tesla vehicle, while the latter is the charge limit target. However, this range is not rigid because that won’t be practical.
The state of charge depends on the mileage of the car. A Tesla owner with more distance to cover on their way to work can’t have the same state of charge as one that covers significantly less distance.
This is another essential factor to consider, and it varies across Tesla models. For instance, the battery capacity of the Tesla Model 3 ranges between 50 and 75 kWh. On the other hand, the Tesla Model S has a battery capacity of 100 kWh.
The battery power or capacity variance explains why the Tesla Model S consumes more energy than the Tesla Model 3. If you charge a Tesla Model 3, taking the above state of charge into account, it will last longer than the Tesla Model S.
Also, consider the type of battery, a Lithium-ion battery never uses the full charging efficiency, so you may get 90% of the battery capacity. If we’re using the Tesla Model S, that means at a 90% charging efficiency, the car gets 90 kWh (kilowatt hours) of energy.
Tesla Energy Requirements
This entails calculating how much energy is needed to charge the battery of the Tesla Model, considering the state of charge and the battery capacity. The amount of electrical energy needed to charge the battery of the Tesla Model S is the state of charge x battery power.
The average state of the charge = 80% – 20%, which is equal to 60%. This will be divided by 100 to give us 0.6 for the calculation.
The battery size at 90% charging efficiency is 90 kWh.
Using these numbers above, the amount of electrical power needed to charge the battery of the Tesla Model S is 90 kWh x 0.6 = 54 kWh. The total energy consumption will come in handy when calculating the number of solar panels required to charge a Tesla.
Solar Panel Design Overview
This involves several sub-factors, such as the solar panel overview, solar panel efficiency, solar panel rating, environmental defects, inherent defects, and solar inverter defects.
Solar Panel Efficiency
The more efficient a solar panel is (the ability of its solar cells to convert energy from the sun to electrical energy), the fewer panels you’ll need for your solar project. This comes down to the type of solar panels you intend to use. When it comes to efficiency, the recommended choice is monocrystalline panels. Solar panel efficiency is also directly affected by the environment and other factors, which we’ll look into later.
Solar Panel Rating
The power rating of a panel simply referees to how much power a single solar panel can generate. The rating varies depending on the solar panel. While some solar panels have a rating of 100w or 200W, some may have a rating of 250W or 300W. This affects how many solar panels you’ll need to charge a Tesla because the higher the rating of the panel, the fewer solar panels you’ll need.
Solar Inverters Defects
The inverter is an important part of the solar system because, without it, the unstable spikes in power can damage your Tesla. The inverter is responsible for power conversion (converting the energy from the solar panels to a stable and constant current that charges your Tesla car).
This may sound surprising, but solar panels are not efficient as advertised. Many solar panels advertise an efficiency rating ranging from 20W to 30W, but it’s about 12% efficiency. This means a lot of solar panels, even top-quality ones, offer about 30% of their advertised efficiency. Does this mean you’ll need more solar panels to compensate for this shortcoming? Not exactly; the manufacturer has already considered these defects.
This refers to environmental factors that can affect the efficiency of the solar charger. These factors include;
- Things that obstruct your solar panels from receiving direct sunlight
- A cloudy weather
- Low temperatures (seasonal or night-time)
Sometimes, the environment won’t be on your side, and this will affect the energy output of the photovoltaic cell. This gives us a variable we’ll refer to as degradation or decline in efficiency.
How Many Panels To Charge a Tesla?
We’ve determined our energy requirement, which is 54 kWh. Now, we need to calculate how many solar panels in closed-loop energy systems we’ll need to fulfill that on a daily basis. Let’s list out the data we’ll be using for the calculation.
The formula for this is simply the total kilowatt hours (energy requirement)/peak sunlight hours/panel rating. Let’s assume that the peak sunlight hours are 6 hours and the power rating is 400W. We already have our energy consumption which is 54 kWh (54,000 watts)
So, this will be 54,000 watts/6 hours/250 watt-hours = 9,000 watts/400 watts
The number of panels = 22.5 (approx. 23) solar panels to charge the Tesla Model X.
How Can I Charge My Tesla With Solar Power?
Definitely not by connecting the solar panels to your Tesla battery, not if you want to preserve your battery. What you need is a solar charging station for your vehicle, and to build that in your home, you’ll need the following;
- Solar panels
- Solar inverter
- Solar battery
- An EV charging station
- A solar charge controller (this preserves battery life by regulating the charge to the Tesla battery)
How to Setup a Solar EV Charger for your Tesla?
- Install the number of solar panels you need (this has already been determined based on the figures we used for the calculation)
- Connect these solar panels to the battery to accumulate energy from the sun that your EV charging station will tap from for charging your Tesla
- Install the solar charge controller and connect it between the solar lithium-ion batteries and the solar panels
- Install and connect the inverter to the solar panels to convert DC power to AC power
- Install the EV charging station (where your car will park for recharging). We recommend using a location with adequate exposure to direct sunlight.
Benefits of Consumer Renewable Energy for your Tesla
Provides Clean Energy
Solar power provides clean energy for your Tesla, which means no addition to our existing carbon footprint. Charging your Tesla with solar panels promotes environmental sustainability.
Save Money on Electricity Bills
Imagine the electricity costs you’ll incur if you decide to power your EV charging station with power from the grid. That will be a lot of money. Though the initial costs of installation of a solar panel system will cost a lot, it will save you a lot of money in the long run because the system is low-maintenance and very durable.