Beyond the solar module: Optimizing system performance and maximizing returns

A photovoltaic system is comprised of multiple components and depends on good design, efficient system architectures, proper installation and maintenance practices. But this is not all: once a system has been designed and developed, it will have to deal with constraints and other requirements related to connecting to the grid.

Meeting these challenges requires a holistic approach that combines the study and application of optimal components (both materials and processes) in order to ensure the optimal performance of a system.

To get the maximum benefit out of your solar system, these key aspects should be taken into consideration before design and installation:

A) Balance of system components
B) Monitoring, operation and maintenance
C) Grid connection

Balance of System Components

The positive or negative effect of the Balance of System (BOS) on your PV system performance depends of the system design and component choice.

Research which power electronic options are available and best suited to each of the PV markets (residential, commercial, or utility scale). The Balance of System typically accounts for half of the system costs plus the maintenance efforts.

According to a new report by Lux Research “Shorting Out the Myths of Solar Power Electronics: What Fits and What Fails” there are three key classes of inverters and power optimizer configurations in each of the market segments:

• Microinverters best suited for the residential market segment
• String inverters for the commercial segment
• Central inverters for the utility segment

Each of these components is selected according to factors such as: reliability, cost, system/product efficiency, maintenance and bankability. Emphasis is given to the reliability and lifetime of the devices.

Monitoring, Operation and Maintenance

The basics of monitoring include measuring your productivity and verifying the performance of your system.

In EPRI’s white paper “Addressing Solar Photovoltaic Operations and Maintenance Challenges,” we learned that PV power plants are not maintenance free and require a regimen of continual monitoring, periodic inspection, scheduled preventive maintenance and service calls.

In fact, this research found that combined fixed and variable Operation and Maintenance (O&M) expenses run between 1% and 5% of all-in project costs for PV plants located in the United States. Meanwhile, in Europe, which supports a more advanced solar economy, O&M costs tend to be 50-100% higher than those in the United States, given a generally greater embrace of O&M activities and their scope.

The paper also presents an overview of the various commercially available monitoring options, along with their related advantages and disadvantages.

Grid Connection

Many challenges arise from plugging a project into the grid. Short circuits, fault current, reverse power flow, the need to accommodate bidirectional power flow and penetration of non-dispatchable variable generation are some of the key technical constraints affecting renewable generation connection capacity on Ontario’s electricity system.

Ontario Power Authority (OPA) strongly advises developers to investigate options for connecting projects to the grid and to determine whether connection capacity is available before submitting an application to the Feed-in Tariff program.

OPA has created an online tool with these questions in mind:

Take a look at “Connectivity Availability Resources”