Size Matters

Power plants and the global success of photovoltaics

In the past, global growth in photovoltaics was primarily sustained by small and medium-sized installations with an output below one megawatt peak. PV power plants with an output of over one megawatt - or even more than ten megawatts - were the exception. Since 2007, this has fundamentally changed. Falling technology prices and the rising costs of fossil fuels are making solar parks increasingly attractive for large investors.

Unlike small roof-top installations, large PV power plants generally feed into the medium voltage grid. In addition, PV power plants with an output of more than one megawatt are almost exclusively free-standing. A survey conducted by the internet service revealed that, since 2008, approximately 2,000 PV power plants with an output of over 200 kilowatt peak (kWh) were built and taken into operation. Among them, over 1,000 solar parks have outputs of more than one megawatt peak (MWh). Many of them were built in sections, each of which represents an independent power plant.

Annual installed power output capacity worldwide for the period from 2005 to 2009, sorted by power class

Number of large-scale photovoltaic power plants installed annually during the period from 2005 to 2009, sorted by power class

In 2008, pv power plants made the breakthrough. With an annual output of over 2.9 gigawatts (GW) per year, large plants supplying 200 kilowatt peak (kWp) or more made up more than half the total output of all PV plants installed worldwide in 2008 - according to this total is 5.5 GW. Power plants exceeding ten megawatts furnished over one gigawatt all told.

In 2009, 1.6 GW were installed globally. This decrease can be primarily traced back to altered subsidy conditions in Spain. But large power plants still had a share of almost a quarter of all output installed. This clearly shows that solar parks significantly contribute to the global success of photovoltaics.

In 2010, the German government announced significant cuts in the feed-in tariffs for large solar plants. Nevertheless, on a global level, framework conditions are steadily improving: Rising cell and module efficiencies will cause the price of solar power to continue to fall, and this is further helped by the severe price drops in solar technology seen since late 2008. Costs for modules and cells fell by one third over the course of 2009. Module prices are expected to fall by another third by 2012.

In particularly sunny regions such as Spain, the Middle East, North Africa, the southern States of the USA, India and parts of China, modern solar modules are on their way to achieving grid parity. And even in countries situated further to the north such as Germany, France or the Czech Republic, grid parity is within reach and is expected within the next five years.

Economic viability the deciding factor

Project planning and management, installation and the operation of large PV power plants present new challenges for planners, investors and bankers alike. Precise analysis of the technical, financial, fiscal and legal details can make or break a project, especially for plants from approximately 350 kWp upward, which require an investment of at least one million euros.

Quality assurance, standardization, location-specific plant layout and intelligent integration into the medium voltage grid for grid connection are indispensible if the project is to be financially feasible and generate sufficient yield in the course of its twenty-year life span. The larger the plant, the more likely it will be that the economic viability of the project, rather than the client's credit standing, will determine whether the bank will grant funding.

Large-scale PV power plants (> 200 kWp): cumulative power capacity (%) as market share of all PV power capacity annually installed (MWp)

Large-scale PV power plants (> 200 kWp): annual power capacity (%) as market share of total PV power capacity annually installed (MWp)

PV power plant in Kolitzheim (Germany) with an output of 1.8 MW

Measurement of characteristic curves as part of performance evaluation