Super Big List of Solar Power Facts
Here’s a super big list of solar power facts, listed under prominent categories.
Solar Panels
- Solar panels can be classified into crystalline (monocrystalline and polycrystalline) and thin-film panels. In 2015, polycrystalline panels account for over 70% of global PV market share.
- Even though solar power plants are usually thought to have a lifetime of 25 years, solar panels can work for many more than 25 years, some times even beyond 40 years.
- Ingress Protection rating (or IP Rating) of a solar module junction box represents the protection the solar module has against dust and water. IP 67 protection ensures that the junction box is completely resistant against dust and temporary immersion in water. IP 65 represents a lower level of protection against these factors.
- While the grade of a solar panel matters significantly, there are no markings anywhere on a solar panel as to what grade it belongs to.
- While a 1 kW solar power plant will require about 100 sqft (approx 10 sqm) of area, of this, solar panels alone require only about 60 sqft or about 60% of total. The rest of the area are needed for spaces between panels, space for cables, inverters etc.
- If your location has regular rainfall, you need to clean the panels much less frequently as the rain does the work for you most of the time.
- Panels usually come with two guarantees – a 25 year guarantee on performance and a 10 year guarantee on the physical product
- A typical 300 W panel weighs about 20 Kg (about 45 pounds)
- Unless you have major space constraints, you might not need panels of very high efficiencies. Going for efficiency ranges around 16% makes sense in most cases
- The warranties provided by the manufacturers will only hold good as long as they are still in business. Hence going for panels from manufacturers of good repute becomes a critical need.
- Thin-film panels usually perform better than crystalline panels at low lights and high temperatures . However they are usually heavier, occupy more space and also calls for additional labour costs.
Solar Power Plant Generation
- Poor orientation of solar panels could result in generation losses of even up to 75%!
- Trackers can increase the solar power generation by up to 25%, and in select cases, up to 30%
- Single axis trackers are quite sufficient in regions located near to the equator
- As of 2016, the current tracker technology does not allow retrofitting them on existing mounting structures
- A 1 kW solar power plant at a location with excellent solar radiation can generate up to 5 units/day on average, or about 1800 units/year.
- Capacity Utilization Factor (CUF) and Performance Ratio (PR) are two parameters that are used to evaluate generation data of a solar power plant. A 1 MW solar power plant at a good sunshine region can show CUF levels of 17-18% and Performance Ratio of 75-80%. Solar plants with trackers can even see CUFs of 21%.
- Solar panels generate less at high temperatures and can potentially generate more at low temperatures!
- Having a power substation far away from your solar power plant can significantly increase the cost of power plant, owing to the cost of grid extension from the power plant to the substation
- Leaving the panels uncleaned for over a year can alone cause a generation loss higher than 10%
- Solar power plant installers should be able to give the owner a performance guarantee for the first year of operation along with the penalty clauses applicable in case the generation is not met.
- Solar power plants in regions with high solar radiation can generate twice as much electricity on average as power plants in regions with low solar radiation. Location is thus of vital importance for a solar power plant.
Solar Inverters
- Solar inverters come in three main forms – central inverters, string inverters, and micro-inverters
- While everyone talks about solar modules, it is the solar inverter which is the real brain of a solar power plant
- The inverters are the components that are most likely to fail and therefore local service support from the manufacturer becomes a necessity in most cases
- Inverter breakdown can cause the entire power plant operations to shut down
- A clean working environment is essential for inverters as they are prone to breakdowns if exposed to a lot of dust and other particles
- Inverters with high ingress protection rating (> than IP 65) are to be chosen for outdoor installations
- Inverters are made to automatically shut down or work at lower efficiencies when exposed to high temperatures
- Inverters come with an anti-islanding feature, by which the grid connected inverters are made to shut down during a local grid failure
- Solar inverters can be air cooled or water cooled
- Inverters usually come with a 5-year product warranty, which can usually be extended to 7 or 10 years, of course at a high premium.
- Inverters are usually over-sized as the actual generation from the panels under real life conditions will be lower than the rated capacity
Solar Mounting Structures
- Solar mounting structures are usually made of steel. They could also be sometimes made of Aluminium
- Galvanization of steel mounting structures ( with thickness about 80-90 microns) is almost a must for it to withstand the elements for 25 years
- Solar mounting structures installed should be able to withstand wind speeds of around 150 kmph
- These mounting structures should have a minimum ground clearance of around 3-4 inches to protect the panels from floods and other issues
- The quality of the nuts, bolts, and other fasteners used in these structures are also critical
- Some customers opt for elevated mounting structures, making room on their rooftops for other purposes
- There are non-penetrating mounting structures available in the market. These are favored by customers who have an aged roof and do not want to damage it. However, these structures are not advisable for installations in high wind zones.
Solar Power Plant Cost
- Even though the cost differences between the solar components are not significant between countries, a solar power plant installation in developed countries costs a lot more than that in developing or underdeveloped countries. This is mainly owing to the higher cost of labor in these countries.
- Unlike many conventional power sources, almost 90% of the total cost involved in setting up and operating a solar power plant for 25 years is spent upfront! (takes into account time value of money).
- Solar panels alone account for 50-60% of the total cost of the solar power plant.
Solar Power Plant Cables
- Solar power plant cables are designed not to be just weather-resistant, but also UV resistant.
- Copper cables are usually employed on the DC side of the power plant whereas Aluminium cables are employed on the AC side.
- DC side cables are usually passed through cable trenches or conduits in order to minimize exposure to harsh atmospheric conditions.
Solar Power Monitoring Systems
- These days, what is popular are string monitoring systems, which can identify faults specific to an array, unlike a central monitoring system which cannot specify the array where the problem occurs.
- Monitoring systems can analyse data from the inverters, string combiner boxes, weather stations and other recording meters
- These monitoring systems can raise alerts to the O&M personnel in case faults occur – helping in quicker repairs
- Increasingly, a good amount of cloud-based analytics are being integrated to solar power monitoring systems.
Solar Power Storage
- Unless you use batteries, solar panels alone cannot supply 100% of power for your home or office
- Using battery for storage can as much as double the cost of power from solar power plants
Rooftop Solar Power
- If your location is in the northern hemisphere, the solar panels on your rooftop should ideally oriented towards south. If your location is in the southern hemisphere, these should be oriented towards north.
- Solar panels are typically tilted in accordance with the latitude of the region
- The age, type, and load-bearing capacity of the roof play a big role in rooftop solar power plants
- While in theory solar panels can installed on even the sides of the buildings and not just on the rooftops, the potential generation from these panels is so low that they are not economically attractive (with the level of technology advancement as of 2016)
- A class of panels called BIPVs or Building-Integrated Photovoltaics has made
Ground Mounted Solar Power
- As of mid 2016, while there are multiple claimants for the world’s largest ground mounted solar PV power plant what can be said is that the largest ground mounted plant at a single location is beyond 500 MW.
- Ground mounted solar power plants cost anywhere between 30-50% less than typical rooftop solar power plants.
- String inverters are being increasingly adopted in ground-mounted utility-scale power plants as EPCs and developers are getting aware of their wide range of benefits in comparison to central inverters. The benefits include increased system reliability (through use of more MPPTs), better system monitoring and lower O&M costs.
Solar Power Plant Maintenance
- The smartest and the easiest way to maintain a solar power plant is to clean the panels regularly with water!
- The suitability of water used for cleaning the solar panels has to be tested for parameters like pH level, hardness, salinity etc.
- Vegetation management around the panels is also as important as cleaning of panels
- Visual inspections by trained personnel alone can make a huge difference in generation
- Maintenance of a solar power can be made more effective through regular monitoring of data provided by the monitoring system that is usually deployed at solar power plants.
- SCADA monitoring systems with IoT (Internet of Things) platforms are getting popular in solar. This state-of-the-art innovation combines superior data acquisition capabilities with advanced analytics to help reduce turnaround times and unwarranted energy losses.
- Usage of security systems can help protect your power plant from thefts and vandalism
- It is always best to leave solar power plant maintenance to seasoned professionals
- Ensure that there are no loose cables or connectors in the power plant
Others
- A 1 MW solar farm could contain as many as 4000 solar modules! A 100 MW solar farm could hence have up to almost half a million solar modules.
- A 1 MW solar farm typically takes up 5 acres of land area. Usage of solar trackers can increase the land required by an extra 1 acre.
- Though thin film solar panels earlier were made from amorphous silicon, as of 2016, thin film solar modules are predominantly made either from a combination of CdTe (Cadmium Telluride) or CIS (Copper Indium Selenium)
- Today, it is possible to implement a solar power plant without any upfront cost through what are variously called the BOO (Build Own Operate) model or PPA (Power Purchase Agreement) model.
