Reliable power with renewable energy

The power transmission and distribution systems in Europe provide such high standards of reliability for the supply of electricity that we cannot even conceive an outage lasting more than a few minutes. We hold long debates on the advantages and disadvantages of various types of power generation technology, and the impact of renewable installations on network operations, electricity prices and overall system stability. We have concerns about the safety of nuclear energy, the amount of emissions from coal-fired power stations, mining limits, purchase prices from renewable sources etc. Everybody has an opinion, no matter whether they present it actively or merely anonymously on social networks. In short, we enjoy the luxury of being able to choose the source of power to light up the bulb on our bedside table in the evening.

Energy self-sufficiency as a choice and a necessity

We have the option of going ‘off-grid’ and building an energy self-sufficient house, even though this is not yet financially viable, and we have to pay disproportionately more to achieve a level of comfort which is comparable to network energy. However, the option exists, and increasing numbers of people are making use of it. The intensity of the debate on the suitability of microgrids, which will be self-sufficient, has increased along with the growing load on the network because of the transmission of large outputs (for example, the number of wind turbines in the north of Germany and the significant consumption in the south of the country). They can run in the islanded mode of operation, if necessary, and will therefore consume whatever they produce or they can assist the system.

But what about regions of the world which do not enjoy the luxury of choice? There are more than one billion people in the world who do not have electricity at all, let alone are able to choose its source. This trend will not change in the foreseeable future due to the high rate of population growth. Those who live in remote communities (such as the original inhabitants of Australia and America), and people living in the mountains far from civilisation and in villages in China and India often only get any electricity due to the use of diesel motor-generators. These machines represented the best possible solution in their day, and they continue to be a very widespread standard solution. ComAp, a company with Czech roots, has supplied areas without electricity with control systems for generators for more than 25 years and in doing so has enabled these areas to gain access to electricity 24 hours a day.

Integration with unconventional energy sources

A diesel motor-generator is structurally relatively simple and maintenance-free to a certain extent, as it “merely” requires diesel and oil, it is reliable and it functions without the presence of an operator, provided it has a good control system. Nevertheless, it would be short-sighted not to expand the energy supply options for users to include renewable sources in a period when the development of new technology is booming and the pressure on reducing the production of emissions and greenhouse gases is high in the name of the fight against global warming. The advantages are indisputable – a reduction in the amount of air pollution, a reduction in diesel consumption and cheaper operations without a negative influence on the safety and reliability of the power supply.

The owners and operators of generators often must upgrade their existing control systems, if they want to integrate their gen-sets with renewable energy sources. Most frequently, this involves combinations with photovoltaic panels and/or wind turbines. Recently, many customers have also been considering the option of using batteries, which can significantly reduce the operating period of the gen-sets, provided the system has been well-designed regarding the load. As such, the gen-sets do not have to idle as a backup against a power outage or the complete interruption of the power supply from the renewable source due to a lack of wind or overcast skies. The appropriate size of the renewable source in relation to the load and the installed capacity in the gen-sets is critical for ensuring a high degree of effectiveness of operations and securing a relatively fast return on the investment outlaid when purchasing the renewable source and the battery.

The ComAp control system not only ensures the problem-free connection of gen-sets with the renewable source, but it also maximises the use of the power from the renewable source and maintains the level of the load on the motor-generators within the permitted limits. It guarantees the reliability of the supply in the case of a power outage by means of the immediate start-up of the gen-sets which then ensure the continuous supply of power to the end users without the risk of a blackout.

The article was originally published on oEnergetice.cz:

http://oenergetice.cz/obnovitelne-zdroje/microgrids-obnovitelnymi-zdroji-energie-ano/