By S.Sivathasan –
A 73 fold global leap in 12 years is the performance of Solar in the present century. For the stellar story to continue what impels and what impedes? Principally, declining cost of Photo Voltaic (PV) fuels growth. Capacity Factor (CF) not rising in tandem has kept back spectacular expansion. Now both are receiving redoubled effort most conspicuously from scientists. The year 2013 may be the watershed year. The prospects are more than promising.
The unit price of electricity to the end beneficiary, the consumer has been the critical determinant in the choice of energy source. Governments as well as investors in power have been watchful over recent decades about declining costs of PV generation of solar power. The great performers in this exercise were scientists whose innovations opened new vistas. Technologists gave shape to the inventions and took development forward thereafter. The result has been a dramatic reduction in the cost of solar generation.
Photo Voltaic Costs
PV module costs have fallen from $4 per Watt in 2006 to below $1 in 2012. These prices have fallen 80% since 2008, with 20% in 2012 alone. A fourth of the decline is accounted for by fall in silicon prices. Silicon price of $130 per kg in 2008 is forecast to be $25 in 2013. A 67% decrease in costs of modules is predicted between 2011 and 2020. In this evolution, 75% is attributed to ‘experience’ ie, sharing of knowledge through interaction and could be even collaborative effort. The above factors have made PV solar quite competitive when compared to other major sources.
A thorough and protracted study to calculate the direct costs of energy was made by a body of professionals and the outcome was published in July 2012. The methodology employed was to bring the calculation to a common denominator of delivering 1 trillion kWh of energy.
The study yielded the following results for cost per kWh in US cents: Hydro 3.3; Nuclear 3.5; Natural Gas 3.7; Coal 4.1; Wind 4.1 and Solar 7.7.
The total cost of installing capacity necessary for the above delivery was in billion $: Hydro 32.8; Nuclear 34.9; Coal 41.4 and Solar 76.8. When it comes to pro-rata cost of installation, it is highest for Nuclear at 5 times more than for Solar. Yet the unit cost of 1 kWh of Solar is more than double that of nuclear. This vast difference is attributed to the contrast in Capacity Factor of 90% for nuclear and 18% for solar. The CF for the latter is influenced greatly by the Intermittency Factor. Massive research and innovation are needed before solar can become more competitive and achieve grid parity. When Intermittency Factor (IF) constraint is overcome with a consequent trebling of CF, the whole mix of energy source in power development is bound to change. A brief duration is forecast for this transformation.
Photo Voltaic Growth
Global increase of PV generation from 5364 MW in 2005 to 102,156MW in 2012 flowed from this price environment. The critical factor to stimulate speedier future growth is Grid Parity (GP). Solar reaches parity when it stands as an equal with other sources without subsidies or Governmental support. As of now among six sources, Hydro is cheapest at 3.3 US cents per kWh and solar is costliest at 7.7 US cents. Despite the disparity in costs, Solar has registered appreciable deployment particularly in the last three years, because of cost reduction with the added advantage of pollution avoidance.
Great advances in technology are expected in 2013 and going steadily up to 2020, when real Grid Parity ie, without hidden costs, tax credits or subsidies will be reached. This breakthrough will be made when the present Capacity Factor (CF) ie (actual as a percentage of potential) of 20% or less is more than trebled. It is the Intermittency Factor (IF) – caused by nightfall, weather patterns, clouds- that induces heavy capital investment in PV. It is as much as seven times compared to hydro. Put differently, it takes 700 MW of solar installed capacity against 100 MW of hydro. This contributes to high unit price of solar.
It is sought to cross the IF through research in energy storage. With recent developments in Concentrated Solar Power (CSP), Capacity Factor can be increased up to 75% with current technologies that are cost effective. It is said that ‘solar salt’ batteries can retain over 90% of captured heat for up to 24 hrs. This efficient storage system allows electricity round the clock. Gemasolar a solar plant in Spain with a capacity of 19.9 MW was commissioned in May 2011. The first one of its kind in the world, it is 24/7 and has a CF of 63%. It is high cost but it opens up possibilities for further research and innovation. When GP barrier is crossed and unit costs are brought below other sources, the stage will be set for exponential growth of solar. All these developments may be seen within the next 5-7 years.
The performance of solar in 2012 signals the turning point in global PV development. The consequences for the future are profound. In the use of solar power, drastic global changes have taken place in deployment as well. The dominance of Europe in the PV market is ceasing in 2013. It declined from 74% in 2011 to 55% in 2012. In the current year, momentum is shifting to the developing world with China gaining swift ascendency. Year on year increase of 34 GW is forecast for 2013. This growth is estimated to reach 48 GW in 2017. This is forecast under a Business As Usual (BAU) scenario which means without major reinforcement of support mechanism. Under a different scenario which is Policy Driven (PD) where administrative barriers and grid connection procedures are removed, 84 GW increase in 2017 is estimated. In two different scenarios, the cumulative projections are 288 GW and 422 GW. Perhaps 350 GW, 3.5 fold increases on 2012, is likely.
There are quite a few un-understandables about the power mix in Sri Lanka. Till 2010, when world had 42% coal fired electricity, Sri Lanka had nil. When the world had 16% hydro, Sri Lanka had 45% which reflected the use of abundant water resources. Yet there was no price advantage to the consumer. For exploiting wind energy which too is abundant, capacity installed is a meagre 50 MW. Even by 2013, solar power on the grid is only 1.2 MW when sunlight is plentiful.
Huge technological advances in solar and wind together with consequent cost reductions in their exploitation are in the offing in the current decade itself. It appears that Sri Lanka is poised to reap unplanned for benefits accruing from procrastination.