Antinuclear

The importance of data centers to the average citizen should not be underestimated. They are vital for even the most common daily function – from a simple internet search to a bank transaction. Their importance can even extend to, for example, the monitoring of the electricity delivered to one’s home.

But data centers are accused of being environmental villains due to their exorbitant consumption of energy, so reducing their environmental impact is vital. In this context, photovoltaic generation is an interesting alternative to free cooling, and especially suitable for tropical regions such as Brazil.

Using the wrong metricEcological footprint (ecofootprint), according to WWF Global, is connected to the impact of human activities, measured according to the production area and the amount of water needed to produce goods and assimilate the waste produced.

Data center efficiency is usually rated by PUE, a parameter conceptualized by the US, the EU and Japan to establish a single metric to assess the energy efficiency of data centers. The concept is not new, because the relationship between useful energy and invested energy is used in many other processes.

The calculation of this indicator is based on the relationship between the energy consumption by the installation as a whole (total energy) and the energy consumption exclusively by IT equipment (IT energy). Like any indicator, PUE may be called into question, but it remains a useful metric nonetheless.

It did not take long for the cooling system to be considered the greatest enemy of PUE; as a consequence, its efficiency has become closely related to its reduction. There is nothing more tempting than getting something for free; for instance, a data center that could potentially be cooled by nothing more than the forces of nature. Since this is not possible, the solution is to decrease a good percentage of energy consumed by central chilled water, taking advantage of free cooling, thus decreasing PUE………

Free energy, not free coolingThe concept of free energy emerges as an alternative to free cooling, on the grounds that it is more suitable to the Brazilian reality and to other countries with similar weather. It is related to power generation using any renewable energy source that has been obtained directly from nature through an environmentally sustainable process. This solution, as well as free cooling, aims to improve data center effectiveness and reduce the ecofootprint from data centers in general. Because of the distributed generation and the ability of interaction between the minigeneration and the energy provider, free energy has become a feasible concept.

Taking photovoltaic power as an example of free energy, when data centers are transformed into generation plants, they may apply this energy to the grid and offset it – not only from an energy standpoint but also economic. Once the concept of free energy is settled, it is inserted into another new term – EcoPUE – bringing a new idea for calculating PUE that is now even more environmentally friendly and presents a sustainable aspect, where the reduction of energy consumption in the data center is linked to the subtraction of the energy generated by the photovoltaic generation system. This renewable generated energy is called ‘free energy.’

Use what works

The increased demand for processing and storage of data, together with the environmental problems caused by high energy consumption, are forcing data centers in Brazil, and elsewhere, to seek more technological solutions and become increasingly green, using energy more efficiently and sustainably while providing a quality service to customers

. A combination of existing technology and techniques, along with new government legislation in Brazil, are now in place, so significant improvements have already been achieved. As an alternative to free cooling, the use of photovoltaics is increasingly being seen as a viable option in countries with a high solar radiation index – like Brazil – where renewable energy can be obtained for free from the natural resources available on the planet.

The concept of EcoPUE demonstrates that greater efficiency from a data center can be enforced with the use of photovoltaic generation, thus reducing their environmental footprint.

Paulo Cesar de Resende Pereira is director of Fox Engenharia e Consultoria in Brazil

This article is translated from the Portuguese-language section of the latest magazine at Datacenterdynamics.es    http://www.datacenterdynamics.com/power-cooling/tropical-sites-need-solar-power-not-free-cooling/95907.fullarticle