Download ppt - Chapter 9 — System Sizing PowerPoint ® Presentation Chapter 9 System Sizing Sizing Methodologies Sizing Utility- Interactive Systems Sizing Stand-Alone

Chapter 9 — System SizingChapter 9 — System Sizing

Chapter 9 — System SizingChapter 9 — System SizingPowerPoint® PresentationPowerPoint® Presentation

Chapter 9Chapter 9System SizingSystem Sizing

Sizing Methodologies • Sizing Utility-Interactive Systems • Sizing Stand-Alone Systems • Sizing Multimode Systems •

Sizing Hybrid Systems • Sizing Calculations • Load Analysis • Critical Design Analysis • DC-System Voltage • System Availability •

Battery-Bank Sizing • Array Sizing

Sizing Methodologies • Sizing Utility-Interactive Systems • Sizing Stand-Alone Systems • Sizing Multimode Systems •

Sizing Hybrid Systems • Sizing Calculations • Load Analysis • Critical Design Analysis • DC-System Voltage • System Availability •

Battery-Bank Sizing • Array Sizing


Sizing strategy for stand-alone systems starts at the load side and proceeds backward to the array.Sizing strategy for stand-alone systems starts at the load side and proceeds backward to the array.


Sizing interactive systems begins with calculating the peak array DC power output, which is then derated for various losses and inefficiencies in the system to arrive at a final AC power output.

Sizing interactive systems begins with calculating the peak array DC power output, which is then derated for various losses and inefficiencies in the system to arrive at a final AC power output.


Interactive-system sizing is very flexible because the utility can supply extra energy to the system loads and receive excess energy from the PV system.

Interactive-system sizing is very flexible because the utility can supply extra energy to the system loads and receive excess energy from the PV system.


Stand-alone systems must be carefully matched to load requirements to avoid reducing load availability or producing more energy than is needed.

Stand-alone systems must be carefully matched to load requirements to avoid reducing load availability or producing more energy than is needed.


A load analysis tabulates the various kinds of loads and their power and electrical-energy requirements.

A load analysis tabulates the various kinds of loads and their power and electrical-energy requirements.


Load power and energy requirements can be easily measured with inexpensive meters.

Load power and energy requirements can be easily measured with inexpensive meters.


Load requirements include the power demand and electrical-energy consumption for all the expected loads in the system.

Load requirements include the power demand and electrical-energy consumption for all the expected loads in the system.


The total DC-energy requirement is determined from the requirements for the DC loads (if any) plus the requirements for the AC loads, taking inverter efficiency into account.

The total DC-energy requirement is determined from the requirements for the DC loads (if any) plus the requirements for the AC loads, taking inverter efficiency into account.


A critical design analysis compares the load requirements and insolation for each month to determine the critical design month.

A critical design analysis compares the load requirements and insolation for each month to determine the critical design month.


DC-system voltage is chosen in proportion with the array size and to keep the operating current below 100 A.

DC-system voltage is chosen in proportion with the array size and to keep the operating current below 100 A.


System autonomy is approximated from the local peak sun hours and desired system availability.

System autonomy is approximated from the local peak sun hours and desired system availability.


Increasing system availability significantly increases the size and cost of the system.

Increasing system availability significantly increases the size and cost of the system.


The battery-bank sizing worksheet uses information from the load analysis to determine the required size of the battery bank.

The battery-bank sizing worksheet uses information from the load analysis to determine the required size of the battery bank.


Due to the allowable depth-of-discharge, low temperatures, and high discharge rates, the amount of useful output in a battery bank is less than the rated capacity.

Due to the allowable depth-of-discharge, low temperatures, and high discharge rates, the amount of useful output in a battery bank is less than the rated capacity.


The amount of available capacity from a battery bank depends partly on the operating temperature and discharge rate. These factors may have different effects for different batteries.

The amount of available capacity from a battery bank depends partly on the operating temperature and discharge rate. These factors may have different effects for different batteries.


Battery labels list the rated capacity of the battery and important safety information.Battery labels list the rated capacity of the battery and important safety information.


Batteries are configured in series and parallel to match the battery-bank rated capacity needed to produce the required output.

Batteries are configured in series and parallel to match the battery-bank rated capacity needed to produce the required output.


The array sizing worksheet uses insolation data and load requirements to size the array.

The array sizing worksheet uses insolation data and load requirements to size the array.


Actual array output is often less than rated output due to soiling, shading, and higher operating temperatures.

Actual array output is often less than rated output due to soiling, shading, and higher operating temperatures.


Modules are configured in series and parallel to match the array rated capacity needed to produce the required output.

Modules are configured in series and parallel to match the array rated capacity needed to produce the required output.