Solar Electric Enery System - MYTHS and FACTS

In this article I would like to present to you the myths and facts pertaining to owning a solar electric energy system. This is just an attempt to offset some of the expectaions of consumers and give them a realistic understanding. Being a solar energy system integrator I have come across questions like how fast can a solar energy system payback or what is the ROI or how much savings can be achieved by going solar. It is these questions that prompted me to write this post and let the many potential buyers know the real cost involved in owning a solar electric energy system.

To begin with let us first see how much electricity will a solar energy system produce.

How much electricity will a solar energy system produce?

A 1 kW solar power system will produce 5 kW hours per day, on average over the year . This equates to approximately 1,800 kilowatt hours (kWh - Units) per year in Indian region. This also depends on a number of factors, such as orientation, partial shading, temperature of the panels etc. An average 3 bedroom home uses 15 - 20kWh (units) per day, but this will be different for everyone. Have a look at your most recent electricity bill. You will find an indication of average usage; this average can be used to find your consumption per day average.

If for example a 3 bedroom home uses 15 KW (15 units) a day then for one month it uses 450 units. And for two months the usage is 900 units, as per Tamilnadu electricity tariff, for usage above 600 units the per unit cost is Rs.5.25. When you invest in a 1 KW solar energy system you can get 5 units a day. In Tamilnadu according to new tariff, for usage above 600 units the charge per unit is Rs.5.25. So for 5 units you get from your 1KW system, 5 x 5,25=Rs.26.25 savings per day. On average we get about 300 sunny days a year, so 300 x 26.25=Rs.7875 savings per year.

Now, a 1 KW solar energy system cost around Rs.2,20,000 to Rs.2,35,000.

This system will have xx number of solar panels of capacity 1000 watts or little above, with warranty.
One charge controller reputed brand with warranty.
A battery bank of minimum 400 AH to store solar power.
A 1500 to 2000 watts sinewave inverter.
Balance of system - connectors, cables, fixtures etc.
Installation and commissioning charges will be extra.

This above system will produce 5 units of 230v AC current a day and so a saving of 5 units per day.

Benefits of Solar Electric Energy System

Personal Benefits
1) You get electric energy almost all the time with out interruption.
2) With a right solar energy system from a knowledgeable supplier you can run all the AC and DC electrical gadgets at your home for life long without damage to your gadgets.
3) It is a non polluting, silent, renewable power source. As long as the sun shines you get power supply which can be stored for one or two days backup with a properly sized storage battery bank.
4) According to the amount of energy (in units) produced the proportionate amount of money (tariff per unit) will be reduced from your electricity bill.
IMPORTANT NOTE : But this is not a gain the reason for which I will let you know towards the end of this post.

Environmental Benefits
1) It is clean, renewable, silent and non-polluting.
2) When you use solar electric energy system your contribution on co2 emission is less. Since you are not using generators you are not using fossil fuels and so no co2 emission.

These days everyone talks about saving our planet, environment protection, green energy, clean energy, silent power et al. But in practice it looks like no one is concerned about it. Because in case they are really worried about the planet, the slightly higher investment involved in geting a solar energy system will not deter them from going solar.

The solar energy system you plan to own is just like buying a car according to your choice and affordability - an economy car or a luxury car or a limousine. You buy this for your need and comfort. There is no savings in it. You buy air-conditioner, home-theatre, washing machine and N number of gadgets. You spend for all these things for your comfort. You even buy a gen set, diesel gen sets 50KV or 100KV. You invest money on the gen set and when there is a power cut you switch it on and you start your contribution of co2 emission to the environment, in addition to using and paying for diesel. But the point to be noted here is that you are not really indifferent towards the environment but you want uninterrupted power supply.

What is in it for you
Solar electric energy is really the best power source in the world. It is silent, eco friendly, green power. But still, this too, you need to buy for your need and comfort only. And not for profit or saving money.

Anyone interested in clean environment, silent continuous power supply and comfort in his lifestyle and can afford to own can go for solar energy system.

When you invest in a 1 KW solar energy system you can get 5 units a day. In Tamilnadu according to new tariff, for usage above 600 units the charge per unit is Rs.5.25. So for 5 units you get from your 1KW system, 5 x 5,25=Rs.26.25 savings per day. On average we get about 300 sunny days a year, so 300 x 26.25=Rs.7875 savings per year. This money you save in 5 years time from the solar energy system need to be spent for replacing the batteries. (There are EXIDE and few other batteries available with 5 years and more life). Your investment for 1KW system is approximately Rs.2,20,000 to Rs.2,35,000. From this you save, in five years, approx. Rs.40,000. But once in 5 years you need to replace batteries by spending about Rs.40,000 for 4 batteries of 150AH.

So do not dream on saving big with a solar energy system. You should buy the solar energy system for your comfort only. It is similar to owning a car or a home theatre system or any other lifestyle equipment at home. But only the owners of the solar energy system can feel and experience the comfort and additional benefits it provides like how their equipments are safe from surge, spike, line interference, lightning and a very quiet operating conditions. While using a solar energy system you are more comfortable and environmentally friendly at the same time. And it is your part in saving the planet.

Incentives
Of course you will get an incentive from state government and central government TEDA. But to get this you first need to buy and install a solar energy system. Then after inspection from the government agency you will be eligible to receive incentive.

I welcome any feedback on this topic. Please send your comments to nag@nagimpex.com

 Sizing your Home Solar Energy System

Whenever you think of installing a solar power system for your home the first question that comes to mind is how big a system do you need and how to find it out. Before answering that question we need to consider two important things.

Firstly, what percentage of your home’s power do you want to get from the solar energy system. Is it 100% or just about 50% or so or just for back-up during power cuts.

Secondly, the per day power consumption of your home.

With the above two information known you can easily decide on the size of the solar power system you need.

It is really easy to calculate the per day power consumption (in units) of your home. To begin with take your past year’s electricity reading card or electricity bill and add the total amount for one year and divide it by 6 or 12 to find out the bi-monthly or monthly power consumption.

If, for example, the two month reading is 600 units and the amount is Rs.xxxx, then the daily power consumption is got by dividing the total units consumed in two months by the total number of days. That is 600 units / 61 days, which is approximately 10 units a day. This 10 units consumption per day might be from a mixed load that can consist of lights, fans, TV, music system, fridge, washing machine, mixer, grinder, phone charger etc. For the above power consumption you need a 1KW (one kilowatt) solar energy system for your home.

The 1KW solar energy system will provide 6000 to 8000 watts power a day or 45 to 55 Amps DC current a day, which can be stored in the battery bank to connect to the inverter through a charge controller. And you can use a 1.5 KVA to 3 KVA inverter to power all the 230V AC loads. With this setup you can run all you AC equipments and appliances such as lights, fans, TV, music system, fridge, washing machine, mixer, grinder, phone charger etc.

And this system costs approximately Rs.2,20,000. Plus the one time expenditure of installation charges, wiring and cost of mechanical mounts according to site requirements.

NOTE: Please note that with the above system you can’t use gadgets which are rated as 1000 watts or above, for example storage water heater, iron box, air conditioner, hair dryer etc. To run these you would need a higher capacity solar power system.

The above example is just to give you an idea of how to calculate the size of the solar power system you need for any particular use.

If you just need to use 50% of your power from solar system then you can choose a smaller system accordingly. Since solar power systems are modular you can expand and increase the system’s capacity as you need at any time in future.

Or if you only want to use solar power for back up purposes during power cut, then mini solar power kits are the best choice. They are both affordable as well as easy to install.

In my future posts I would give detailed information on the following topics:
1) Solar Panel Selection
2) Charge Controllers – its importance and uses
3) Inverters – Sinewave, Modified Sinewave
4) Batteries – Wet, SMF, VRLA, GEL and High AH very long life batteries
5) BOS (Balance of System)
6) Do-It-Yourself Solar Power Kit

 10 Watt DIY Solar Home Lighting Kit w/USB Port

Product Description:
The kit consists of a 10w solar panel, charge controller, battery box with 4 DC outputs for 4 bulbs & 1 USB port for cahrging mobile phone, PM3 player etc., 4 super bright LED bulbs with connecting wires with holders.

Specification:
Solar Penel: 10 watt High Efficiency monosilicon panel, with 6 meters wire
Battery: SMF Lead Acid Battery, 12V7Ah
With switch on the battery box and an indicator to show the battery power status
Lamps: 4 nos. of high power super bright 3.3w LED bulbs, each with builtin 24 SMD LEDs
5 meters of cable with each LED bulb, with screw type holder with inbuilt switch
With USB Output to charge mobile phones, MP3, MP4 players etc.
With 4 changeable adapters for charging most popular mobile phone models such as Nokia, Samsung D900, Sony-Ericcson, Moto V3
Charging Time: Around 8-10 hours to full charge
Lighting Time: Around 5-6 hours when fully charged (to light all 4pcs of bulbs at the same time)
Around 3-4 hours after one-day charged

The below mentioned life is under normal condition and to be used for the intended use.
Bulb life 20 years, 5 hours a day. Battery life 2 years to 2.5 years. Solar Panel life more than 25 years. Charge controller life more than 10 years.

We are introducing this and higher power DIY Mini Solar Power Kits that are really simple to install and use, just plug in and you are ready to go. These kits are an affordable solution to the annoying power cuts. If you are interested please contact us for further details.