Investment in installing solar cells How many years will it reach the break-even point?

Believe that everyone who wants to install a solar cell system It must certainly be curious that after we have invested in installing the solar cell system. That system will generate returns for us. Until the payback within how many years?

I must say that the payback of the solar cell system It depends on many factors such as installation price. suitability for installation installation size and behavior of electricity usage, etc., which we cannot say clearly that it will be able to pay back within how many years. Because sometimes there may be problems in the system, such as equipment damage during use. Or external factors such as the weather, the sun is not strong, this will cause the solar cell system to generate electricity and generate less returns than it should be.

However, the engineer can be evaluated at the beginning which uses almost the same calculation principles everywhere Let’s look at the principles of calculation.

First of all, we would like everyone to understand that on average A solar cell system can generate energy for about 4 hours/day because of course the sun doesn’t shine steadily throughout the day. and as mentioned above There is a possibility that the device may have already deteriorated.

Instructions for calculating the break-even point in the solar cell system!

Before we calculate to find the “Break-Even Point” for the solar cell system. We must first know which variables to use in the calculations. Let’s see.

1. Should know the electricity bill during On-peak and Off-peak

(On-peak = 4.2 baht Monday – Friday from 09:00 AM – 22:00 PM)
(Off-peak = 2.5 baht Monday – Friday from 10:00 PM – 9:00 AM and Saturday – Sunday, public holidays all day (except holiday compensation)

2. Should know that 1 unit of electricity = 1 kWh (kilowatt hour)

3. The installation fee will be calculated according to the number of watts (Watt). For example, if we want to install a 100 kW solar cell, the price is 30 baht/Watt, so the installation cost is equal to (100 kW or 100,000 Watt x 30 baht) = 3 million baht.

Let’s take a closer look at how the concept of “Break-Even Point” is calculated?

Suppose we install a 200 kW solar cell with a price of 30 baht/Watt. Therefore, the installation cost is equal to (200 kW or 200,000 Watt x 30 baht) = 6 million baht.

Then let’s look at the variables to be calculated. Let’s start by looking at our install size. How much electricity can be produced per day? From the above (200 kW x 4 hours/day electricity generation) = 800 kWh

Therefore, we will save electricity costs (800 kWh x daylight cost 4.2 baht) = 3,360 baht/day. And in 1 year will save electricity cost (3,360 baht x 365 days) = 1,226,400 baht/year *based on factory that works every day (7 days/week)

Another variable is the maintenance cost that is around 10% of the system which must be deducted. (Saved electricity cost/year 1,226,400 x 10% maintenance cost) = 122,640 baht/year and deducted together equal to (Saved electricity cost/year 1,226,400 – Maintenance fee 122,640 baht/year) = Electricity saving 1,103,760 baht/year year

So this assumption will be able to return the investment in (installation cost 6 million ÷ energy saving effect 1,103,760 baht/year) = 5.4 years only

Tax incentive (BOI) can tax exemption 50% of project value for 3 years

In addition, for the installation of solar cells in factories or industries. can claim up to 50% tax exemption from BOI

For example, the installation cost of 6 million baht can be entitled to 50% tax exemption as the period of 3 years can be calculated as follows: (Installation fee is exempt from BOI tax 3 million ÷ 3 years) = Discount on installation fee 1 million baht/year

Then we went to see what tax rate to pay. Suppose we have a tax burden of 20%, we take (1 million x 20% discount on installation fee) = tax reduction of 200,000 baht/year.

Equals that (Tax exemption period 3 years x Tax reduction per year 200,000 baht) = 600,000 baht, yes. We can reduce the value of the solar cell installation project by 6 hundred thousand baht, so the investment we have to actual payment is (installation fee 6 million – 6 hundred thousand baht) = 5.4 million baht

So this assumption will be able to return the investment in (installation cost 5.4 million ÷ energy saving effect 1,103,760 baht/year) = 4.8 years only

However, the assumption of calculating the “Break-Even Point” from the installation of the solar cell system is as follows. Said is a preliminary concept only. because the real result may pay back capital quickly or later depends on various factors which we have explained at the beginning of the article However, the cost of electricity is more expensive. It will make the return on investment (ROI) higher accordingly, resulting in faster payback.

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