Weather forecasting is becoming big business in the power sector and no more is it solely the realm of national meteorological organizations but a business critical service offered by specialist companies who have developed the requisite skills and sector specific solutions. [Engerati-Here come the Meteorologists! Business Critical Forecasting for Renewables]
Grid management, integration of renewables and energy trading are all able to benefit from improved forecasting and give the edge to the owner, operator or trader who is prepared to make the necessary investment.
As an indication of the level of activity, Engerati caught up with no less than four companies in this space at E-world 2016 Energy & Water – all with some inevitable overlap in terms of the services offered but also each having their individual niches.
Focus on grid operation
“More and more, energy is weather dependent and knowing the weather means knowing the energy supply,” says Matthias Kittler, Energy Business Unit Director at the MeteoGroup, claimed to be Europe’s largest private sector weather data provider.
MeteoGroup has a strong focus on forecasting for grid operations. “We approach it from two angles,” says Mr Kittler. “One is to support operators getting the most out the existing infrastructure through detailed temperature and wind forecasting for specific powerlines. The other is to prevent against risks such as storms or for example winter icing of powerlines.”
He adds that the company is a strong believer in visualization of data. “We want to make it as easy as possible for customers to understand the data and to enable them to make confident decisions easily.”
Unlike wind which generally shows less variability, solar forecasting presents specific and very local challenges as even a single cloud can alter the output of a PV plant, with potentially significant impacts for both operators and traders.
Increasingly commonly deployed are ground-based cameras to photograph and predict cloud movements over individual solar plants. French company Reuniwatt, which is based in Reunion Island in the Indian Ocean and Paris, takes this one step further, with a strong focus on supplementing these with predictions from imagery from satellites.
“Different technologies are needed for different time horizons and ultimately it’s a statistical process,” explains Reuniwatt meteorologist Frederik Kurzrock. “One needs to combine the forecasts statistically to make the best of them and for example, with satellite imagery we can improve the intra-day trading forecasts.”
Renewable hybrid systems are gaining in popularity especially in emerging markets and environments such as rural areas and islands where they are able to provide round-the-clock power countering the intermittency of the solar or wind. [Engerati-Hybrid Power Systems And Their Role In Emerging Markets]
French forecasting company Steadysun has developed a sky imager, now in the second version, as an easy to use plug and play solution to use alongside hybrid systems. The imager takes photographs of the sky on a minute by minute basis, which are processed by the company’s forecasting algorithms to provide half hourly forecasts, updated every minute. The solution enables optimal management of the system, which may include solar, fuel generators and storage.
“The aim is to provide a near real-time management tool,” says Steadysun’s VP Sales and Marketing, Jean-Marc Eyraud. “For locations with several assets, it enables maximizing the use of the solar resource while optimizing the use of storage systems and fuel generators. If a cloud comes in then power from a battery can be supplied if necessary, or if there is a large bank of clouds then you know you will need a generator. Properly integrated in an EMS, the average cost of the energy produced by the system can be reduced by up to 40%.”
Forecasting with big data
Bernd Kratz, CTO of the the German forecaster Enercast, highlights the power of big data and cloud computing in forecasting.
“We collect approximately 150Gb of data a day from different weather services, which would normally require a supercomputer to process. With the systems we have developed we can upscale the compute power in the cloud to 1,000 or more computers to enable forecasting for 400,000 power plants on a 15-minute basis.”
Mr Kratz claims an accuracy of 97-98% in forecasting for all the German PV plants. However, all of the companies point to the need for greater forecasting accuracy on shortening timescales. For renewables trading 15-minute products are becoming increasingly commonplace for example in Europe, requiring forecasting on at least the same period as a minimum. [Engerati-Renewables Disrupt The Energy Trading Market]
Accuracy is one part of the equation and the other is reliability. Says Meteo’s Mr Kittler: “Ensuring that customers have their forecasts when they need them, morning, noon and night, is also key. Together accurate and reliable forecasting paves the way for further penetration of renewables.”