New papers are published

Published: 21 Sep 2016

We are pleased to announce that the two peer-reviewed papers describing the Renewables.ninja models were published today in the journal Energy. These papers describe the underlying models that generate wind and solar time series data, demonstrate their validation across Europe, and then use them to study the impacts of wind and solar power across Europe in the near future.

In Pfenninger and Staffell (2016) we modelled the hourly output of solar panels across all the countries of Europe. We assembled a database of hourly power output from over a thousand real solar panels across the continent, and use those to discover how well the MERRA and SARAH weather data is able to replicate solar panel output. We derive correction factors that improve the quality of our simulations and then use these to investigate how solar power will impact on Europe's power systems as installed solar capacity increases.

We find that the increasing deployment of solar PV across Europe will lead to substantial day-by-day, season-by-season, and year-by-year fluctuations in power production. For example, demand net of solar power has the potential to be negative in Germany, and will fluctuate sharply from one day to the next depending on the level of cloud cover. On a typical summer day in a future Germany with 115 GW of PV (three times today’s capacity), power demand net of PV production would range from a minimum of +11 GW on a cloudy day to –30 GW on a sunny day. In general, PV power exhibits a strong seasonal trend — the same “115 GW PV” Germany would still have a minimum of +30 GW of net demand on a typical winter day, even in the sunniest of our 30 years of simulated data. Yet a sunny day in winter can yield more power output than a cloudy day in July. These patterns of power output from PV panels through the year will substantially change how the rest of the power system will have to operate.

In Staffell and Pfenninger (2016) we modelled the hourly output of wind farms across Europe, considering both the current farms installed today, and those that are planned to be built in the future. We find that when simulating current farms, the underlying weather data needs to be corrected in order to yield realistic values for energy output, and these correction factors vary from country to country. Sadly, by ignoring these corrections, previous studies have over- or under-estimated wind farm output by as much as 50%.

We perform a 20-year simulation of Europe’s current wind farms, and find that they should operate with a 24% capacity factor during an average weather year, with countries ranging from 19.5% (Germany) to 32.4% (Britain). By then simulating the farms that are currently under construction or in planning, we find that Europe’s wind productivity could rise by a third, up to an average capacity factor of 31%. This is because new farms are being built using taller turbines placed further out to sea, where wind speeds are significantly higher.

The full version of our data, with validation and corrections, are available as both pre-processed data sets (covering all countries in Europe for 30 years) and as a live web-tool for performing your own simulations of renewable energy anywhere in the world.

We hope that making high quality data on renewable energy technologies freely available will help break down a significant barrier in studying this crucial area, saving other researchers from duplicating efforts, allowing them to answer their questions faster, and hopefully to start asking new ones.

For further info, please see the press releases about this work:

Or read the articles themselves (available open access):