ICE turn on thermal plant despite having reservoirs filled

Entity claims that renewable electricity production became insufficient

Impact of the measure could be seen in electricity rates from July

April 22nd,2015

The Instituto Costarricense de Electricidad (ICE) fired its thermal plants to generate power, despite its four reservoirs recorded levels higher than projected at the time water.

The entity uses fossil fuels (the most expensive and polluting source) after successfully avoided for 86 days: from December 22 2014 to March 17, 2015. In that period, generating covered almost 100 % by clean resources.

That "renewable" record lurched March 18. Thereafter, the country relies on thermal plants "steadily" according to Juan Quesada, mayor Energy Regulatory Authority of Public Services (Aresep).

Only between March 18 and April 6 were generated 33,400 megawatt hours (MWh) heat; the majority (96.8%) by Garabito, the most efficient of all eight of the ICE project.

How does this affect citizens? The use of oil for generation could cause an increase in electricity rates in the adjustment to be made in July variable cost of fuel (CVC).

This quarterly adjustment depends on how much fuel (bunker and diesel) purchased the ICE to operate its thermal.

For example, since it was not necessary to use this source during the last quarter, the application of CVC on 1 April led to a fall of up to 15% on electricity bills. In December, January and February the generation run of river grew 55% and wind production doubled over the same period of 2014.

Besides being pollutant, the thermal energy is often more expensive than renewable. In May, a private generator sold kilowatt hour (kWh) biomass ¢ 37; almost three times cheaper than the average cost of kWh produced in Garabito.

Why go back to the heat? According to Luis Pacheco, manager of the ICE, clean resources are "insufficient".

"Use all available renewable resources is made; from the time these become insufficient to meet demand, consider thermal generation, "said the chief.

Pacheco's statements appear inconsistent with hydrological conditions this summer, which have allowed to store large volumes of water and remain favorable. By Sunday, the levels in the four reservoirs (Arenal, Cachi, Angostura and Pirrís) were higher than expected.

El Arenal recorded 541.66 meters above sea level (ms nm), although projected 535.33 meters. Cachi was 986.10 (instead of 985.70 meters); Angostura, 575.93 instead of 573.50 m asl, while the water level in Pirrís is almost two meters above expected.

In any case, the heat should be the last option for the ICE. Before exploit, should ensure that no megawatts at cheaper prices in the Regional Electricity Market (MER). According to Pacheco, this obligation was fulfilled in 86 "renewable" days and continues to be fulfilled.

The Nation consulted Quesada of ARESEP, if prices in the MER are indeed more expensive than handling the Garabito plant, but at press time no answer.

Read more: 'La Nación'