Large grid-connected PV systems can provide the energy needed by many customers. In urban areas, PV arrays are commonly used on rooftops to supplement power use, feeding power back into the grid. In rural areas, they may be the sole source of electricity, used to directly power DC equipment or to charge a storage battery. Large PV power stations can cover tens or hundreds of hectares and have outputs of up to hundreds of megawatts. The drive to reduce GHGs and increase the sustainability of power supplies is leading many governments to offer incentives for solar energy to improve the return on investment, with attractive feed-in tariffs available for private installations connected to the grid. PV cells are made from layers of semi-conducting material, usually silicon. When light shines on the cell it creates an electric field across these layers. The stronger the sunshine, the more electricity is produced. Groups of cells are mounted together in panels or modules that can be mounted on a roof. Each panel is rated by its DC output power measured in kilowatts peak (kWp). This is the rate at which it generates energy at peak performance in full direct sunlight during the summer. The efficiency of a panel determines the area needed to produce the same rated output: an 10% efficient panel will have twice the area of a 20% efficient panel with the same rating. An inverter is used in order to convert the DC output to AC to feed into the grid, which reduces the efficiency further. The biggest challenge the industry faces is to deliver higher efficiencies at affordable cost, and several companies have begun to embed ICT electronics into PV modules in order to optimise performance.
There are a number of systems available for improving the output of solar PV arrays by ensuring that the maximum possible electricity is generated from the available sunshine. These include:
Monitoring PV systems is essential to achieve maximum energy production and to detect breakdowns. Using Pacific Controls Managed Services for Critical Assets Monitoring to monitor and control PV panels allows the use of MPPT, monitoring and fault detection for each module individually. Pacific Controls managed services will alert staff quickly to system outages or underperformance. Data monitoring tools are also essential to capture historic production data, and to produce verifiable data to qualify for payments from renewable energy schemes such as REC payments. There are several possible strategies depending on the output of the installation and its nature:
Solar PV suppliers can offer their customers wireless monitoring systems using Pacific Controls cloud computing service so that owners can check the performance of their PV array using a web browser from any location. This is valuable both for commercial solar power stations, which need to maximise returns and for residential users who wish to check performance from their living rooms.
Solar PV suppliers can offer their customers wireless monitoring systems using Pacific Controls cloud computing service so that owners can check the performance of their PV array using a web browser from any location. This is valuable both for commercial solar power stations, which need to maximise returns and for residential users who wish to check performance from their living rooms. The system includes the data monitoring module, which is installed on site, and provides user access to the PV panels performance information from any location on a password protected website. The system offers more information and flexibility than a stand-alone data logging meter and communication interface, but also without the cost and inconvenience of installation and maintenance of a separate metering system.
Small residential systems may have minimal data analysis requirements other than total energy production; larger grid-connected power plants can benefit from more detailed investigations of performance Pacific Controls Managed Services for Critical Assets Monitoring integrate both the PV solar system and inverters for all installed PV systems in a global portfolio from any location. It carries out performance analysis using advanced data mining techniques and artificial intelligence, combining the panel data with that from external sensors such as pyranometers and provides proactive and predictive FDD.
Using Pacific Controls Managed Services for Critical Assets Monitoring, solar panel manufacturers can offer their customers monitoring and management services to ensure that solar PV installations are generating power whenever there is sunshine at their location.
They can offer predictive maintenance services to minimise downtime. The service operates through a single interface that connects all the PV panels deployed globally allowing them to analyse data across their whole portfolio. This allows them to have an on-going relationship with panel users and provides a central data depository for analysis that will enhance R&D.
Connecting solar panels to Pacific Controls ICT Enabled Managed Services For Business Process Integration optimises every step of solar PV generation. Efficiency monitoring ensures that the panels are tracking the sun, the inverters are operating at peak efficiency and that there are no losses from module mismatch or under voltage operation. Users can also predict the power likely to be generated in the future, based on past performance and weather forecasts. Pacific Controls advanced FDD capabilities ensure that potential faults are identified before they occur and that problems are dealt with in a timely manner. The systems will have higher uptime and users will be proactively notified of any deterioration in performance.