If you’re looking into installing solar, one of the biggest questions is what size your solar panel system should be. It’s very common to install enough panels to cover as near 100 percent of your power needs as possible, as this is how you’ll maximize your savings. But is there any advantage to sizing your solar panel system to produce more power than you as of now need? For the vast majority, the response is no. But, there are certain circumstances in which it’s a good idea to install a larger system than you currently need.
What’s the meaning of “oversize” a solar panel system?
When somebody’s thinking about “oversizing” a solar panel system, it can mean two distinct things-
- Installing more panels than they have to meet their power needs
- Installing a solar panel system that has a higher power output rating than the solar inverter it’s connected to
Why you shouldn’t install more solar panels than you need?
Oversizing solar system won’t receive enormous benefits for most people, particularly in case you’re not using the extra electricity your system produces. Here are the top reasons why you shouldn’t include more panels than you need.
Utilities won’t pay you extra for your additional power
Most utility service providers offer net metering. With net metering, your service organization will credit your bill for any excess power generated from your solar system. But a larger solar system may mean more net metering credits for you. If you’re not utilizing the credits, it’ll either exist as a continuous credit on your bill or will expire after a certain period. The specific point of how long you’ll get the opportunity to keep net metering credits relies upon your service provider’s policy.
A misconception is that utilities will pay your cash for any excess power generated from your solar system. But the larger part of service organizations won’t pay individuals out for net metering credits. In the rare instance that your utility will buyout your additional net metering credits, the rate they will pay for them will be significantly lower than what you initially got for the net metering credit (which is ordinarily retail cost).
At last, the extra upfront cost of installing an oversized solar panel system won’t be worth it if you cannot take advantage of that extra electricity. The additional cost will extend your payback period for going solar.
Your solar panel system will upfront cost
A larger solar panel system is going more upfront cost. Because larger solar systems require more panels, a larger inverter, extra racking, and more work from your installer. The additional cost will rely upon what number of watts you’re including onto your solar panel system. But it generally isn’t worth it if you’re not using all the electricity being generated.
The Interconnection process is difficult
When you apply to connect your solar system to the grid, the utility service provider will audit your previous power utilization to check whether the system proposed is sized properly. Utilities the whole way across the country will frequently deny interconnection requests when the system proposed is larger than what your utilization history shows you need.
Some service providers will be stricter about giving permission to a large system than others and may make a special case in case you’re anticipating oversizing for a consistent explanation. Always check with an installer to see whether your utility allows oversizing, and if so how much.
Extra incentives may not be worth the additional expense
If you install a larger system and paying more money, then you’ll be eligible for higher upfront incentives. Most tax credits and rebates are calculated as a percentage of your total expense or based on the size of your system. Some of the incentives also have a cap on the total amount you can claim. There are some performance-based incentives (PBIs) where your incentive amount is directly correlated to how much electricity you’re producing.
For example, in states with solar renewable energy certificates (SRECs), you will acquire more in SREC income with a larger system because you will generate more kWh. At that point, it turns into an issue of whether the additional SREC value is more than the extra upfront cost of more panels. For most of the current SREC markets, the answer is no.
Why you should install a larger solar panel system than you currently need?
When you are thinking about the installation of solar panels, you will go over the decision of how huge of a system you should buy. In this article, we will share with you the top reasons to oversize a solar panel system.
Oversizing a PV array also referred to as under-sizing a PV inverter, involves installing a PV array with a rated DC power which is larger than an inverter’s rated AC output power. It can be a valuable tool for system designers seeking to deliver a maximum amount of energy at the lowest possible specific cost.
An Oversized Solar Panel System Will Produce “Excess Power”
Solar panels rarely produce as much power as their capacity. It is possible to include additional panels with no power being lost. Also, the additional panel capacity helps the inverter to run at a higher efficiency which can almost make up for what is lost. At the point, when the total capacity of the solar panels is greater than that of the inverter the panels are said to be “oversized” or the inverter “overclocked”. Oversizing solar panels not only can save you the amount of money, but it also increases your energy generation when your grid operator limits the inverter size you can install. Under good weather conditions, solar panels are only producing energy when they have access to the sun’s rays. Oversized solar panel arrays will produce more DC power than their inverter turns into AC power and this outcome in the excess power being lost.
Lower the specific cost of energy delivered
By oversizing a PV array, a lower cost of energy can be delivered (lower $/kWh). Oversizing a PV array will increase the expense of PV modules and array racking for a system. Since this can be accomplished without necessarily expanding either the amount of rating of other balance of system components, the increased energy generation is accomplished with a lower $/kW introduced cost. This yields a lower specific cost of energy delivered by the system. An example comparison made using Sunny Design shows that by oversizing a PV array with a 5kW inverter, the yearly energy yield of a system can be increased by more than 28 percent for just an around 10 percent increase in the total cost of installation.
Reduce inverter costs
By oversizing a PV array; the DC energy output of that array can better match the rated AC power of an inverter. This implies that an inverter with a lower AC rating (and lower cost) can be utilized. This can diminish the relative cost of inverters compared to the complete system cost.
Achieve favorable energy output when installing inverters in limited space
Sometimes inverters need to be installed in specific locations, due to limitations from the owner or local electrical guidelines. This may mean it would not be possible to install the number of inverters at a site as would be wanted for a perfectly sized system. By oversizing PV arrays, it may be possible to accomplish nearly a similar yearly energy yield with fewer installed inverters. For example, utilizing Sunny Design, a 100kW PV array with three Sunny Tripower 25000TL inverters (i.e. 75kW of inverters) would produce around 2 percent less energy yearly compared to the same PV array with four Sunny Tripower 25000TL inverters (i.e. 100kW of inverters). This implies that there is just an almost 2 percent lower energy output for 25 percent fewer inverters.
Better match the inverter to the PV array, in the event an inverter needs to be replaced
If an inverter fails once it has exceeded its warranty period and it isn’t always possible to replace it with a similar model inverter. In such cases, an inverter of an alternate AC yield force may be bought and introduced. By introducing an inverter with a lower AC output power, the existing PV array could be better matched to the inverter’s capacity and the replacement cost to the system owner minimized.
Make the most of East-West PV arrays
PV arrays are installed to maximize energy output and as so are inclined towards the equator (south-facing in the Northern Hemisphere, north-facing in the Southern Hemisphere). Sometime the array plane available for installing PV modules with these ideal direction conditions may not be as great as other less ideal array planes. In situations where the area accessible for east and west-facing directions is greater, a PV array may be part of some east-facing strings and some west-facing strings. Since an east and west PV array will peak in output power at different times, it is possible to greatly oversize a PV array (example, install a DC input power equal to the inverter AC output power for each of the east and west PV arrays). Utilizing an inverter’s sizing ability in such a way can deliver greater energy output and a more level AC output every day.
There can be many reasons to install an oversized PV array. Given PV array rarely operates at their rated peak power, oversizing a PV array can utilize an inverter’s rated AC output and deliver a lower cost/watt system resulting in a lower specific cost of energy produced ($/kWh). It is significant for oversizing PV arrays that an inverter’s critical input limits are never exceeded. Sunny Design is the ideal tool to utilize when attempting to design a PV system with an oversized PV array. It is important to consistently conforming to local electrical guidelines and to utilize appropriately qualified system designers and installers.