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Electrical power generated by solar Photo-Voltaic (PV) is one of the best options for sustainable energy requirements but the variability and unpredictability inherent to solar create a threat to grid reliability due to balancing challenge in load and generation. Variability of power represents the change of generation output due to unscheduled fluctuations of solar radiation patterns. Large unscheduled changes in solar power generation are called ramp events which hamper the penetration of variable power in the existing grid. The variability in PV power is not a major issue with small-scale systems, but a large scale grid-connected system needs sufficient statistical analysis to model the power fluctuations to assess the reliability of the system. The variability can be quantified as a measure of dispersion in variable renewable power generation. Though there are different ways to quantify variability, the simplest way to measure variability is using the normalized squared deviation about mean of the actual generation for some time blocks. 

To accommodate variability, the short-term and long-term forecasting became an important tool in asset management, operations and maintenance of PV solar generation. The recent developments of deep learning algorithms in ANN (Artificial Neural Network) based methodologies using NWP (Numerical Weather Prediction) models have created a huge scope in forecasting the solar power generations with acceptable error margins. Since there are computational issues like the uncertainty in the initial value vector of NWP, proper availability of learning vectors in DNN (Deep Neural Network) and choice of proper architecture of DNN, forecasting can be viewed as statistical prediction rather than a problem with deterministic solutions. Thus from an analytical viewpoint, forecasting can be regarded as the temporal evolution of probability distributions associated with variables required in predicting the solar power generation. Predictability can be viewed as the ability to forecast the solar power generation with sufficient accuracy such that penalty due to error-deviation is very small; and predictability can be measured using probability.

Variability of actual solar power generation is the characteristics of solar plant whereas the predictability refers the property of proper forecast models. A good forecast model is that which captures the genuine patterns in the historical data, but does not replicate past events that will not occur again. Though there is a common belief that the high variability of power generation reduces predictability, the predictability of good forecast is independent of variability. If predictability depends on the variability of the solar generation, then either there is some issues in the basic architecture of the forecast model or the forecast system is not running in its full potential.       

-By Abhik Kumar Das, del2infinity Energy Consulting

The recent proliferation of solar installations across the U.S. means balance-of-systems (BoS) components (everything other than the panels and inverters) are coming under wider scrutiny during risk-mitigation inspections.

Lower solar Feed in Tariffs has required developers to look at cost effective solutions to meet project IRR requirements. Trackers are increasingly being preferred by many IPPs, as good trackers are the only Bankable way to meet the IRR target. Decision to be made is which Tracker technology is suitable in terms of cost but at same time, will last for 25 years. Simply compromising on the structure integrity to arrive at lower cost is not prudent.

To fly a plane around the world on solar energy alone was considered almost impossible until Solar Impulse took to the skies last year, setting a new record for the longest non-stop flight*. 

Converting sunlight directly into electricity, the photovoltaic (PV) solar panel industry has dominated the solar generation market recently because of its astounding price drops. Prices have fallen 99 percent in the past quarter century and over 80 percent since 2008 alone. This has also helped to slow the growth of the “other” form of solar, concentrating solar thermal power (CSP), which uses sunlight to heat water and uses the steam to drive a turbine and generator.

Meyer Burger develops solar technology - from wafers to solar PV systems - with the aim of promoting the widespread use of photovoltaic energy and making solar power a first-choice source of renewable energy.

Scientists in South Korea have made ultra-thin photovoltaics flexible enough to wrap around the average pencil. The bendy solar cells could power wearable electronics like fitness trackers and smart glasses. The researchers report the results in the journal Applied Physics Letters, from AIP Publishing.

 

Copper-indium-gallium-selenide (CIGSe) solar cells have the highest efficiency of polycrystalline thin-film solar cells. The four elements comprising CIGSe are vapour-deposited onto a substrate together to form a very thin layer of tiny chalcopyrite crystals.

58 gigawatts of monitored PV will be added to the world’s total in 2016, bringing the cumulative PV monitoring market to 242 gigawatts

Renewable energy deployment in the electricity sector is catalysing efforts to modernise the electricity grid, including the increased implementation of battery storage.

Over the last few decades, there have been numerous reports of degradation of PV modules caused by high voltage stress. This, in turn, generally affects the Energy Yield (EY) and the Return of Investment (RoI) of the PV installation.

The solar energy industry has come of age. Operations and maintenance of existing PV plants worldwide could well exceed 200 GW by the end of 2016. The shift in emphasis from building newcapacity towards optimising the existing fleet is being heralded by a greater focuson safety and asset value. But this evolution is threatened by inertia – doing things the way they have always been done. Oscar Fitch-Roy and Ragna Schmidt-Haupt of DNV GL, the leading global energy advisor, identify several elements of a modernised and holistic approach to solar operations and technical asset management.

GTM Research’s latest report expects 1500-volt architecture to take over the utility-scale solar market over the next few years, citing clear balance-of-systems cost advantages.

Japan and the U.S lead the world in battery storage implementation thus far. However, other countries are also increasing deployment, including Germany and China.

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New inverter maximizes energy harvest from the PV power generation

E-KwBe is a new modular lithiumion based energy storage system which can help to optimize the use of in house solar energy systems, cut the electricity bills and reduce carbon footprint.

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