Solar Energy

Solar power is the conversion of sunlight into electricity, either directly using photovoltaics (PV), or indirectly using concentrated solar power (CSP). Concentrated solar power systems use lenses or mirrors and tracking systems to focus a large area of sunlight into a small beam. Photovoltaics convert light into an electric current using the photovoltaic effect.

Photovoltaics were initially solely used as a source of electricity for small and medium-sized applications, from the calculator powered by a single solar cell to remote homes powered by an off-grid rooftop PV system. As the cost of solar electricity has fallen, the number of grid-connected solar PV systems has grown into the millions and utility-scale solar power stations with hundreds of megawatts are being built. Solar PV is rapidly becoming an inexpensive, low-carbon technology to harness renewable energy from the Sun.

Many industrialized nations have installed significant solar power capacity into their grids to supplement or provide an alternative to conventional energy sources while an increasing number of less developed nations have turned to solar to reduce dependence on expensive imported fuels (see solar power by country). Long distance transmission allows remote renewable energyresources to displace fossil fuel consumption. Solar power plants use one of two technologies:

• Photovoltaic(PV) systems use solar panels, either on rooftops or in ground-mounted solar farms, converting sunlight directly into electric power.
• Concentrated solar power(CSP, also known as “concentrated solar thermal”) plants use solar thermal energy to make steam, that is thereafter converted into electricity by a turbine.

Commercial concentrated solar power plants were first developed in the 1980s. The 392 MW Ivanpah installation is the largest concentrating solar power plant in the world, located in the Mojave Desert of California. Other large CSP plants include the SEGS(354 MW) in the Mojave Desert of California, the Solnova Solar Power Station (150 MW) and the Andasol solar power station (150 MW), both in Spain. The 579 MW Solar Star, in the United States, is the world’s largest PV power station.

How much land is required to setup a 1MW solar power generation Unit?

The land required for a 1 MW power plant setup is around 4.5-5 acres for Crystalline technology and around 6.5-7.5 acres for Thin-Film technology. This is only a rough benchmark and may vary based on technology and efficiency of panels.

What is the life-time of a typical Solar Power plant?

The useful life of a typical Solar Power plant is considered to be 25 years. This is the duration for which long-term PPAs are signed and financial models are built. However, Solar Power plants can run beyond 25 years while producing a lower output. Many Solar Panel manufacturers guarantee an output of 90% at the end of 10 years and 80% at the end of 25 years.

What is the annual energy generated from a 1 MW Solar Power plant?

The usual benchmark for energy generated from a 1 MW Solar Power plant is considered as 1.5 Million units. This is only a benchmark and should not be considered as the actual output for a given location. The amount of actual energy generated from a Solar Power Plant in an year depends on both internal and external factors. External factors which are beyond the control of a Solar developer can include the following:

• Number of sunny days
• Solar Irradiation
• Day Temperatures
• Air Mass

The output also depends on the following internal factors all of which are within the control of a Solar Developer:

• Plant Location
• Usage of Solar Tracking systems
• Quality of equipment used
• Workmanship of the EPC contractor
• O&M activities

What are the various modes under which we can setup a Solar Power plant?

The various modes under which a Solar Power plant can be setup depends on the specific requirement. All the following are valid modes and the costs for each kind of system varies based on various factors:

• Off-Grid Captive Consumption for domestic premises
• Off-Grid Captive Consumption for commercial premises
• Grid Connected (Net Metered) Captive Consumption for domestic premises
• Grid Connected (Net Metered) Captive Consumption for commercial premises
• Sale of Power generated to local Distribution Company (DISCOM)
• Sale of Power generated to 3rd Party consumer (Industry or Commercial entity)

What is the cost of setting up a Rooftop Solar Power plant for domestic or commercial use?

Rooftop Solar Power plants can be broadly categorized into Battery-based and Non-Battery based systems. The benchmark cost set by MNRE for the year 2013-14 for these systems are Rs.90-100 per W for Non-Battery based systems and Rs.170-210 per W for Battery-based systems. More details can be accessed on the following MNRE webpage: http://mnre.gov.in/file-manager/UserFiles/amendmends-benchmarkcost-aa-jnnsm-2013-14.pdf

What size Solar Power plant is required for domestic or commercial use?

Identifying the Solar Power plant size for your domestic or commercial premises depends on the following factors:

• Wattage of appliances to be run on Solar
• Monthly energy consumption from these appliances
• Energy Backup or Days of Autonomy required
• Roof space available for plant setup

Based on these factors, the power plant sizing can be accordingly done at your end.

Courtesy: http://efficientcarbon.com