Most Important Considerations For Designing An Off-grid Solar Power Plant?

Important Considerations For Designing An Off-grid Solar Power Plant


More companies and individuals are switching to solar power systems as the renewable energy industry increases, owing to the evolution of solar designing and calculating tools like solar power system design software for its exact and accurate solar designs and proposals. Solar energy has also received substantial backing from a number of nations. Commercial and industrial enterprises that rely on higher-cost grid electricity are increasingly looking into renewable energy sources to reduce costs.

The term "off-grid" refers to a system that operates independently and is not connected to any utility's power system. This method stores the produced solar electricity in batteries. Although off-grid systems are self-sustaining, they are more expensive since the customer must purchase a battery pack, solar panels, grid box, inverter, charge controller, mounting structure, and system balancing. During the day, the panels create and store energy, which they then use at night. The device is appropriate for locations that experience regular power outages. Off-grid solar systems can provide autonomous and sustainable power generation in rural and isolated places.

The Off-grid Solar PV Applications Programme, one of the Ministry of New and Renewable Energy's oldest programmes, has built up solar house lighting systems, solar street lighting systems, solar lanterns, solar pumps, and solar study lights. Solar pumps, according to the ministry's website, are an important component of the solar off-grid initiative, which provides small and marginal farmers with a reliable irrigation facility. These pumps are being installed in rural regions to replace conventional diesel irrigation pumps. Since 1992, the government has been executing the initiative, and 2.37 lakh solar pumps have been installed in rural regions.

Why Should You Go Off-Grid?

There are several reasons why now is the perfect time to design an off-grid PV system. These include:

  • Solar panels and corresponding equipment are now far less expensive and more efficient.
  • The cost of connecting to the grid is prohibitively expensive.
  • Energy prices are steadily rising.
  • The grid's ongoing reliance on fossil fuels
  • The ambition is to be self-sufficient in terms of energy.
  • Production of renewable energy and sustainability

Sustainability and going green are admirable goals, yet they are frequently the least of our motivations for producing our own energy. Many people are concerned about their energy independence. Concerned about not being connected to the grid, growing energy bills, and opting out of an energy market that does not function for customers,

Off-Grid Solar System Design:

Off-Grid Solar System Design

An off-grid solar power system is made up of several main components. To go really off-grid, your system must include batteries to store the energy you create. It will also require solar panels to generate energy and other technology to connect everything.

A typical off-grid electrical setup will look like this:

  • Solar panels and mounting kits for roof or ground installation.
  • An inverter converts the DC current stored in your batteries into usable AC electricity.
  • Charge controller for managing solar energy conversion.
  • Batteries to store the energy you create.
  • Monitoring solution that allows you to regulate power generation and consumption.
  • Backup emergency generator
  • Network router to connect everything together.
  • Cables, fixtures, and fittings

Off-Grid PV System Calculation:

A solar panel, solar inverter, battery, and system balancing are the four basic components of an off-grid PV system. Solar panels use sunshine to create DC current, which is then stored in batteries. A charge controller is required to run DC applications (12V), such as fans and lights. You'll need an inverter to convert DC voltage to AC voltage if you wish to operate AC appliances (220V). All inverters nowadays function automatically, which means that the electricity generated by the solar system instantly charges batteries and powers appliances. In the event of a power outage, batteries may also power appliances directly.

Most household equipment, such as fans, televisions, coolers, air conditioners, and water pumps, may be controlled by this system. A 1 kW off-grid solar system, for example, is sufficient for a 2–4 BHK home. However, a 3 kW off-grid solar system might be used to power a 1 HP water pump in your home. If you want to run an air conditioner, a 5 kW solar system is the way to go. A 10 kW off-grid solar system should be utilized for business installations such as a shop, clinic, small mill, or petrol station.

It's the most prevalent sort of solar power backup system. During the day, the solar panel charges the battery and powers home equipment such as air conditioners, refrigerators, televisions, and submersible pumps. When the sun isn't shining, the inverter uses battery power to power your household appliances.

Off-Grid Solar System Design Calculation:

Do you want to learn about off-grid solar system design and calculations? To get started, follow these six steps:

Calculate Your Power Requirements:

Arranging a solar system without knowing how much electricity you require is like planning a road trip without knowing how long you will travel or in what vehicle. Now go get some petrol for the journey. How much is it? That depends on your travel distance and petrol mileage. The same goes with solar power. You can't just buy two solar panels and a battery and hope that's enough for your requirements. Enter what you will be powering with your solar power system into our load calculator. You must remember everything that will be powered by your system; seemingly minor modifications might have a significant impact.

Calculate the Number of Batteries Required:

Batteries are designed to be stored at temperatures of around 80 degrees Fahrenheit. The larger the battery bank required for below-freezing temperatures, the colder the space. Each of these options has an impact on the size and cost of your battery bank.

Which battery bank voltage do you require—12V, 24V, or 48V? In general, higher voltage battery banks are employed in bigger systems to lower the number of parallel strings and the amount of current flowing between the battery bank and the inverter. A basic 12V battery bank makes sense if you only have a modest system and want to be able to charge your phone and run 12V DC gadgets in your RV. However, if you need to power more than 2000 watts at once, you should look at 24 volt and 48 volt systems. In addition to lowering the number of parallel strings of batteries, it will allow you to employ thinner and less expensive copper cable between the batteries and the inverter.

Determine the number of Solar Panels required for your Location and Time of Year:

The second portion of our off-grid calculator can assist you in determining how many solar panels you will require for your solar system. After you've determined how much energy you need to produce every day using the load calculator, you'll need to tell it how much sunlight you'll have to gather. The available solar energy for an area is referred to as "sun hours."

Off-Grid Solar System Design Calculation

The amount of "sun hours" refers to how many hours the available sun shining at an angle on your panels throughout the day equals sunlight, as if it were shining directly on your solar panels when they are at their most powerful. Because the light isn't as bright at 8 a.m. as it is at noon, an hour of morning sun counts as half an hour, and an hour from midday to 1 p.m. counts as a full hour. And, unless you live near the equator, the amount of sunlight in the winter is not the same as it is in the summer.

You want to use the system in the worst-case situation for your location, the season with the least quantity of sunlight. This way, you won't run out of solar energy throughout the winter.

Select a Solar Charge Controller:

So now that we have batteries and solar, we need to figure out how to get the power from the solar into the batteries. To figure out what size solar charge controller you need, take the watts from the solar panel and divide them by the battery bank voltage. Add an extra 25% for a safety factor.

With the charge controller, there's a little more to think about. There are two basic types of charge controller technologies available: PWM and MPPT. In summary, a PWM charge controller may be used if the voltage of the solar panel array matches the voltage of the battery bank. PWM can therefore be used if you have a 12V panel and a 12V battery bank. If the voltage of your solar panels differs from that of your battery bank and cannot be coupled in series to match, you must use an MPPT charge controller. You must use an MPPT charge controller if you have a 20V solar panel and a 12V battery bank.

Select an Inverter:

Now that we have effectively charged the batteries, we must make the electricity useful. If you are solely running DC loads directly from your battery bank, you may skip this step. However, if you are powering any AC loads, you must convert the direct current from the batteries into alternating current for your appliances. It is critical to understand the sort of AC power required. In North America, the norm is 120/240V split phase, 60Hz. It is 230V single-phase 50Hz across Europe, much of Africa, and certain nations in South America. Some islands have an unusual combination of the two. Some inverters are switchable between voltages and/or frequencies, while others are fixed. So thoroughly examine the specifications of the inverter you're considering to ensure it meets your requirements.

Whether you do have the North American standard, you must determine whether you have any 240V appliances or if they are entirely 120V. Some inverters can output 240V, and the output can be wired to utilize either 120V or 240V. Other inverters are stackable, with each one producing 120V but producing 240V when coupled together or stacked. Others, on the other hand, can only generate 120V and can not be stacked. Read the specifications again to determine which inverter is best for you.

Balance of System:

In addition to the elements listed above, you will need to choose a few tiny components that are required for the system's balance, such as fuses and breakers that provide overcurrent safety. You'll also have to figure out what size wiring you'll need, which breaker boxes you'll use, and how you'll attach the solar panels.

There are several more minor components required, including:

  • The overcurrent protection fuses and breakers
  • What breaker boxes will be used
  • How will the solar panels be mounted
  • What size wire you'll require

You'll be well on your way to creating, and, more significantly, using, your new off-grid solar-plus-storage system once you've accomplished all six of these processes.