How switching to energy efficient ceiling fans can save almost 25% on total cost solar installation

There is no denying the fact that renewable sources of energy will take over the current sources of energy in the near future. And when it comes to renewable, solar is at the forefront. We are already experiencing an era of change, when on the 7th June, India and United States have signed an agreement to increase the penetration of solar in India. Nothing can be better than an occasion where two countries are working with each other not just to increase trade but to make their countries greener. Reports say that the purpose of this deal is to provide electricity to the rural parts of the countries and to help curb the climate change.

But for all its advantages, Solar has several limitations both in commercial or consumer market, which is hindering its growth. A few of those are listed below:

• The efficient versions of solar panel are very expensive making it a heavy one time investment. Solar panels are mostly used in rural parts of the country where money is a constraint. As we know solar being a heavy investment switching to solar can be something one will put a thought into.

• The power needs to be stored using inverter batteries so as to use it during night. There is a high possibility that one can run out of power if the devices connected aren’t used wisely.

• In cities, directly switching to solar is not a wise option. This is because most of the old devices consume lot of power and solar is manufactured to operate with energy efficient appliances considering the whole point of installing solar in a city is to save energy.

For example, the cost of a combined PV-fan system could be reduced by around Rs. 6750 for a drop in ceiling fan power demand from 70 to 25 W, under the assumption that the current cost for rural solar PV installation is about Rs. 150 per watt-peak. To further illustrate this point, we devised this hypothetical case which shows how switching to low power consuming and energy efficient ceiling fans can bring down the total cost of solar installation.

Case Study:

Let’s consider a case where a new school wants to use solar so as to set a good example to students. Here we will explain 2 scenarios( 1 where the client is installing ordinary ceiling fans, and the other where the client is using energy saving fans.

Scenario 1:

The school has planned to install 100 LED lights and 300 new fans consuming 15 W and 74 W each respectively. In Indian scenario a school will function for 8-10 Office Hours.

Crompton Greaves LED
Power Consumption(W) 74 15
Total power consumption for 300 Fans(W) 22200 1500
Total power consumption for 300 Fans(W) 23700

We find the total power consumption would be 23700 Watts.

Scenario 2

In this case, the school decides that instead of ordinary fans, they will go for energy efficient Gorilla Fans.

Gorilla Fans LED
Power Consumption(W) 28 15
Total power consumption for 300 Fans(W) 8400 1500
Total power consumption for 300 Fans(W) 9900

We find that the total power consumption is 9900 Watts.

Cost of Installation:

Now, we calculate the total cost of installation for both the scenarios:
We assume that Su-kam polycrystalline solar panel of 250W/24v is used to power the above infrastructure. The cost of each plate is Rs 12500

Scenario 1: Crompton Greaves Scenario 2: Gorilla
Total Number of Plates required (Total Wattage/ 250) 95 40
Total Cost of solar infrastructure in INR(Cost of each plate * Number of plates required) Does not include cost of Balance of Systems like Batteries, Inverters etc. 1187500 500000

The difference in cost of installation due to the use of Gorilla Fans is a staggering Rs. 687500. Using the same solar panel with smart appliances the total number of solar panels is reduced from 95 to 40 Solar panels, which is almost 1/3 of the requirement in the case 1. This will decrease the initial capital investment for solar panel from Rs 11.87Lakhs to Rs 5Lakhs.

Now, let us come to the extra cost that is incurred by the customer by installing the energy saving fans as compared to ordinary fans.

The difference of Gorilla Fans as compared to a CG fan is Rs 1250.

Crompton Greaves Gorilla
Cost 2250 3500
Cost of installation in INR 675000 1050000
Difference in Cost in INR 375000
Difference in cost of installation of entire infrastructure in INR (Difference in cost of installation- Cost Difference in cost of fan) 312500

If the investments are seen even with extra cost of the appliances a school will save Rs 3.12Lakhs and the space used for 55 solar panels. Also, it gives an added advantage due to the elimination of windings on the rotor, these BLDC fans are not subjected to centrifugal forces. And because the windings are supported by the housing, they can be cooled by conduction, requiring no airflow inside the motor for cooling. This, in turn, means that the motor’s internals can be entirely enclosed and protected from dirt or other foreign matter.

The combination of PV with a BLDC fan motor can be especially beneficial because PV produces DC current, which is the input needed for the BLDC motor controller. This eliminates the costs of a rectifier, which is typically needed to convert household AC current to DC current for the BLDC motor. Therefore, a super-efficient ceiling fan can considerably reduce the wattage need of a solar home system, which would increase the marketability of solar home systems.

On a concluding note, it’s advisable to all solar power users to switch to BLDC energy efficient Gorilla Fans and LED because without smart and energy efficient technology, switching to solar is not only going to cost you more money, but the returns of the investment will take much longer.