Question

For the system of section 4.8 , use NREL SAM, detailed version, to estimate the array size where the ac annual KWh output is no longer proportional to the array. In order to run the detailed version, you will need to enter a specific module and a specific inverter. Ideally, the module will be a Phono Solar PS350M-24/T module and the inverter will be a Yaskawa Solectria Solar SGI 500XTM 500-kW. Plot your results as a graph of annual KWh versus array size to illustrate where the graph becomes sublinear.

Answer 1

To find where the AC annual kWh output from a PV array becomes non-proportional to its size using NREL SAM, input the specific module and inverter specs, estimate initial array size based on solar insolation and electrical needs, and simulate at various sizes until the sublinear relationship is observed.

Step-by-step explanation:

To estimate the array size for a PV system using the National Renewable Energy Laboratory's System Advisor Model (NREL SAM) where the AC annual kWh output becomes non-proportional to the array size, you would first need to input the specifications of a specific module and inverter, such as the Phono Solar PS350M-24/T module and the Yaskawa Solectria Solar SGI 500XTM 500-kW inverter.

As part of the process, you should calculate the initial array size by determining the daily kWh production needed and dividing this by the kWh/m²/day value which represents the site's solar insolation. For example, if you require 10 kWh/day and have an insolation of 5 kWh/m²/day, a 2 kWp peak system would be adequate. Considering a ballpark figure for losses, an additional 20% may be added to account for inefficiencies.

Creating a plot of annual kWh versus array size requires running simulations at various array sizes and comparing the output to the array size until the point is found where the increase in output no longer matches the increase in array size, indicating a sublinear relationship. This typically occurs as the array size starts to reach the inverter's maximum rated capacity or due to other system constraints.

Answer 2

Using the NREL SAM detailed version with a Phono Solar PS350M-24/T module and a Yaskawa Solectria Solar SGI 500XTM 500-kW inverter, the array size at which the annual KWh output is no longer proportional can be identified through a graph. The point where the graph becomes sublinear signifies the limit where additional array size doesn't proportionally increase the annual KWh output.

Step-by-step explanation:

To determine the array size where the ac annual KWh output deviates from proportionality, the NREL SAM detailed version is employed with specific module and inverter specifications. The Phono Solar PS350M-24/T module and Yaskawa Solectria Solar SGI 500XTM 500-kW inverter are chosen for this analysis. A graph plotting the annual KWh output against various array sizes is constructed to visually illustrate the point at which the relationship becomes sublinear.

In photovoltaic systems, the linear relationship between array size and annual KWh output typically holds up to a certain point. Beyond this point, the increase in array size yields diminishing returns in terms of KWh production.

This deviation from proportionality is crucial for system optimization, helping to identify the optimal array size that maximizes energy production efficiency. The choice of specific module and inverter ensures accurate simulations, allowing for a reliable assessment of the system's behavior as array size varies.