Utility Scale Solar Photovoltaics for Sri Lanka

By K.Gnanalingam - Former Addl.GM (Commercial) CEB.

Utility scale solar power, historically underutilized, is poised for explosive growthThe case for utility scale PV is compelling. As Renewable Portfolio Standards (RPS) are now promulgated in, utility companies are mandated by law to obtain a percentage of their power from sources such as solar PV. Sri Lanka wants to have 10% of all electricity to be produced by renewable by 2010.Why Utility Scale?Utilities understand many of the benefits of solar PV, including timely Day Peak energy production, grid stress relief, capacity factor, favorable permitting and construction timeframes, and growing public understanding and desire to use solar energy. Some utilities already offer ratepayers clean energy such as wind and solar at a premium.But PV must make sense financially. The economic benefits of utility scale solarPV is improving as installed PV costs drop, and solar modules and inverters gain in efficiency. And even at higher costs, solar energy currently benefits from incentives in many regions. As this reduces the import of Costly fuels into Sri Lanka GOSL should look into this in giving such incentives and place the Feed In Tariff for Solar soon. It had been already done for the Wind, Biomass and Mini hydro.Rural solar home systems replace the most costly imported Kerosene. Grid connected Solar Home system in Larger Houses ( Initially they are people who can afford these now with the benefit of Net metering) will generate distributed energy in the Grid thereby reducing the System losses.As the PV industry ramps up to meet growing global demand, manufacturing and production of PV components are bringing well paying jobs and tax base to the workforce and to local regions. In 2008 worldwide implementation of solar PV topped 5.3 Gigawatts of installed capacityBase load energy prices increase roughly 4 to 8% per year. Wholesale kilowatt hour (kWh) pricing during peak are also increasing, as energy demand and fossil fuel costs rise. Because of its fuel source, solar PV produces the most electricity during Day peak and energy is most needed. Solar PV plants provide a reliable and predictable base load year round. PV adds to overall capacity generation for a utility, particularly during March through August. This is the time we face shortage of rain in Catchment areas. This is the time the Air conditioning load is highest. As utility scale solar plants are commissioned, the early assessments indicate capacity factor of solar exceeds that of wind. Solar PV technology is known as an exceptionally reliable source of electricity, having been used on US satellites

since the early 1960’s. Some on the 60’s era solar modules still produce electricity, earning PV the reputation as an “old” new technology. Typically, solar output is reliably predicted using 30+ years of insolation data and now with satellite data of more than 10 years.Putting the Deal TogetherRenewable portfolio standards mandate that utilities source a percentage of their generation from renewable sources. Many states promote solar PV with a specific carve out. This creates a tradable solar credit, kind of a “market-based feed in tariff”, that helps finance solar power plant construction. This is yet to ne done in Sri Lanka.Scalable and Quick to InstallSolar PV plants are quickly permitted and built in comparison to conventional power plants. For example: Some conventional power plants can take as long as 10 years to permit. The Coal plant of CEB took more than 20 years to start construction !Utility scale solar PV plants are being built at costs in the range of $2000 to $3000 per kilowatt, in time frames of 1 to 2 years, and the price is becoming more stable as the industry matures. The capacity of a conventional plant per acre is much greater, but the fuel for a solar plant is free, and makes for a “clean neighbor.” Solar power plants can run with minimal maintenance. This is an ideal situation for Sri Lanka as we usually neglect Maintenance of Power plants. Tracker technology improves both yield and capacity factor. Solar plants can be small to medium, distributed on thousands of residential, school, business and industry rooftops in towns and cities, or very large multi megawatt plants built at sites such as farms, landfills, or former brown fields.

Systems can be installed modularly, and can be added to at later dates. Because it is predictable and reliable, PV works in locations and geographies where solar resources may seem limited. For instance, the world’s largest solar PV market has been in southern Germany, at latitudes in the range of 48° to 50° Solar PV provides energy when it is needed most. The Peak load in those countries is in the day time. Now Spain has the largest Solar PV plants installed in the last two years with the incentives given by the Government.And finally, the environmental benefits of solar PV cannot be understated. Over25 years, the environmental attributes of a 3 MW power plant akin to planting nearly 632,000 acres of mature trees – nearly 1000 square miles.