Wind Power Over Production

It is well know the relevance of Wind Power production in Spain. In some cases, arriving close to 50% of the mix generation (see Figure 1).

As a example, the 28th January 2014, there was a pick of wind power yield, as it is possible to check in the Spanish TSO: Transmission System Operator  website (Red Eléctrica de España).


Figure 1_Wind Power Yield in the Spanish Electric System 28th January 2014// Source: REE

ACER (Agency for the Cooperation of Energy Regulators), published some weeks ago an information which has to be considered.
This information is one study about the integration of Renewable Energies in the Electric System across Europe.
Taking a look in the case of Spain, whit high amount of Wind Power Generation. And being Wind Power, the most important of all Renewable Energies in terms of capacity and generation, comparing with other  Renewable Energies like PV Solar Power or CSP (Concentrated Solar Power).

In concrete, the study explains the amount of Energy, by in this case, Wind Power, it is necessary to manage by the TSO to the Electric System for over generation.

In other words, the amount of power which TSO must to manage for non being able to insert in the system, in consequences of the low demand. 

It is necessary to consider, this situation is happening normally during wind storms and low energy demand.

The study exposed that the Spanish Electric Systems "wasted" 8% of total Wind Power yield during the spring of 2013, in concrete 29th, 30th and 31st March 2013, days of holidays in Spain (see Figure  2).

Figure 2_Wind curtailment compared to demand in Spain, 25th to 31st March (MWh) Source: ACER

If it is compared this data with other countries, Spain has increased the negative progression respect other members of UE. 

If it is taken in consideration 2010 and 2011, the Wind Energy yield "wasted" was only near 1%, and comparing with Italy which "wasted", in some cases near to 5% and averages of 2% in 2011 and more than 1% in 2012. 

At the same time, Germany, UK and Ireland, with results being high than the range of Spain.

Getting in deep about what really happened in Spain for explaining this abnormal situation. It is has to be understood that 2013 was very rainy year. Considering Spain as a country with dry weather, because northern areas have abundant rainfall, but the most of people in Spain lives in Mediterranean coast, where normally suffers dry weather.
 

In contrary, 2013 was a really rainy year in Spain, and in consequence, the hydropower resources was really great, non having the possibility to use storage pump during night. Similarly, the crisis was decreasing the demand of Electricity in Spain from 2008 year by year.

On the other hand, Spanish Electric System  (data updated at end 2013) has 108.148 MW of installed Power (all kind of Energy Production), 0.2% more than 2012, even having a Demand Decreasing. An example for that is, in 2013, the maximum power needed for the complete system was 40.227 MW (27th February 2013). Other point for considering is, those days , Spain is under cold and wind storm.

This means, less than half of the total power installed, even considering 20% of "Security Range" for whatever unusual event, is over capacity. It means, the Electric System does not need it. Then, with this information it is possible to conclude next, for Spanish Electric Systems is not needed around 48.000 to 50.000 MW Power Generation installed. Knowing the cost of that for the public entities and for private investors which made investments in Renewable Energies in time when in Spain was enabled Feed-in-Tariff, overall in Cogeneration plants which right now are not profitability (around 27.000 MW installed).
Looping the loop, 2013 was a year which was even installed Concentrated Solar Energy plants, increasing 15% (2.300 MW) of its capacity, and also, an increasing of 3.2 % of Photovoltaic (2.300 MW) and Wind Power which has been increased 0.8%.

Considering all this information it is easy to think about the issues presented in the Spanish Electric System for the future (see Electric SystemChallenges blog), decreasing demand with over capacity.

Regarding the ACER  information, the study proposed to reinforce the Spanish  interconnection between France, Morocco and Portugal for having more flexibility in cases like exposed. It means, to use the international interconnection to export in whatever case of over production, and then mitigate the possible Electric System collapse by overloading Power Lines and Trafos. See interconnection for 29th March 2013 as example in Figure 3, source:   Electricity Interconnection in South-Western Europe .

Having in consideration the yellow area of Figure 2 (wasting Wind Production), the Electric interconnection of Spain between France, Morocco and Portugal during this day, even having during night hours over production. It is well understood the system exported Electric production to France, but incomprehensibly the system imported Electric production from Portugal, and there was no active intereconnection between Spain and Morocco during night hours (see Figure 3  Hours 02-03 to 07-08). Even the systems imported electricity from Portugal in this critical night hours (of course being a little bit less than other hours).

Of course ACER is recommending it has to be more understanding between all European Electric interconnections and also with Morocco. Because, it is not possible to waste Electric production and at the same time, importing electricity from Portugal to Spain.

Figure 3_ Spanish Electric interconnection in real time jfor 28th January 2014: Source: Electricity Interconnection Wester-South Europe

Nevertheless, it has to be considered to apply the technological resources it has nowadays in the field. Wind Power, it will be able to success with more efficiency and then, overcome the most important disadvantage.

It is well known, the storage systems will be one of the most advantages systems for the Wind and Solar PV Energy achievement. With the feasebility to control the concrete moment to integrate the intermittent  energy. Which sometimes is not needed when is produced, the question is easy, are right now available this conventional storage systems, in terms of profitability. It seems in  some states the technology is taking off. 

But, it is the time for integrating in Renewable Energies investments this technologies, with the cost it represents. May be is necessary to wait more time for being possible to integrate this storage systems in Wind & PV Solar Power projects. Just waiting for more mature technology and then, to get lower cost generation. Because it is well known, the systems are well introduced in the field.

Last news informed about the progression in the new technologies in the storage systems. Researchers has developed a metal-free flow battery which performs also with vanadium flows batteries, reducing the use of the expensive metal and being free of precious metals. And of course, the time and investments will reduce the cost of this storage systems.

Similarly, Demand Response will play one important role, also in this Wind Power achievement. Just for growing the demand during night hours, with incentives for increasing the electricity demand in this hours. When the consumption is less, peak-off hours normally in residential and industrial consumptions (see Figure 4 of the 28th January 2014, peak-off from 2:00 h. to 6:00 h. /Spanish Case - Western Europe Area - latest sunset Europe compare with central and east Europe). Of course, Europe is a little bit in one emerging situation in this topic compared to US.

Figure 4_ Electricity demand tracking in real time, associated generation mix and CO2 emissions_Source: REE (www.ree.com)

The other technology which can help to reduce the "waste" of this electricity generated is EV Charger. Which is able to incorporate inside Demand Response management, and play a great role in the process of smooth the electric load curve. Increasing the demand during the night with the charging of EV, for that, of course, it is needed the implementation of the EV. And, at the same time, the EV Charger in the most of residential consumers. This will reduce the fluctuations and reduce cost of the Electric System operation.

Figure 5_ Inside the Nacelle of one Wind Turbine during Hannover Messe im 2004 where is possible to see the high number of poles in the generator_Source: Javier Sanchez Rios