Power transmission problems and solutions

Power Control
02 Aug 2021

 Electrical power transmission involves the bulk movement of delivering generated electricity from a generation site (1), typically a power plant or renewable sources, across transmission lines (3) to the distribution grid (5) located in populated areas. 

Along the way, step up (2) and step down (4) transformers control the flow of electricity by increasing or decreasing the kV. When generated, electricity will be between 11kV and 33kV. At the transmission stage, it is stepped up to anywhere between 100kV and 700kV, depending on the distance it is required to travel. The electricity is then stepped back down in the distribution stage (5) to meet demand from primary and secondary consumers. 

 

Meeting consumer demand is a delicate balancing act with potential problems occurring at any stage of the process. Understanding the causes of power problems and where they typically occur leads to a better understanding of how to protect your business against them. 

 

Electricity is generated in two main ways, from non-renewable sources whereby fuel is burnt to generate energy and from renewable sources such as wind and solar. At this point in energy transmission, a brownout is a major cause for concern. This may be a result of infrastructure malfunction or load shifting. Brownouts tend to be caused by increased demand for power or extreme weather conditions putting additional strain on the network.

 

On the 9th of August 2019, two UK power stations tripped within two minutes of each other. The loss of generation on this occasion caused the system frequency to drop below 49Hz and as a result, the network had to disconnect some recipients to meet the demand with the available capacity. 

 

Frequency forms one of the foundations of Great Britain’s power system and every generator connected to the high voltage transmission system is synchronised to one another. Just a 1% deviation risks damaging equipment and infrastructure if it persists. As proved 2 years ago, a 2% deviation from 50Hz is enough to bring down power in entire areas. 

 

One of the more common causes of power failure is severe weather. Strong winds, heavy rain, floods, lightning and ice can all damage power generation, transmission and distribution equipment. Power spikes and surges occur when lighting strikes transmission lines causing a burst of energy to be superimposed onto the normal mains power supply.  

 

Although the equipment was designed to withstand most weather conditions, global warming has increased the frequency of extreme conditions. A warmer climate may reduce the efficiency of power production for many existing fossil fuels and nuclear power plants because these plants use water for cooling. Colder water means a more efficient generator. In addition, changes in the frequency and severity of storms and other extreme events may also damage energy infrastructure, resulting in energy shortages.

 

Lightning storms can also cause trees to come down, taking transmission lines down with them. Tree branches contacting power lines and wildlife can also cause a failure of power transmission.  

 

Any problems occurring at the generation stage has a knock-on effect on the rest of the power system and can result in business downtime, damage to critical equipment or in some circumstances such as in hospitals, put patient and staff safety at risk.  

 

The Impact of Smart Technologies on the Grid

Modern technology is also putting greater strain on the grid. The number of people now driving Electric Vehicles (EVs) for example is on the rise. This could cause a real-time imbalance between generation and load, especially at peak charging times such as when commuters head home after work between 6pm and 8pm. 

 

There is also the added risk from those choosing to use third parties to manage their vehicle charging. With charge point operators changing the charging rates of too many EVs at once, the electricity system may be left unable to respond leading to a loss of supply. 

 

Without a properly managed smart charging system for the rapidly growing, power thirsty EV fleet, power generation could fail.

 

UPS Systems and Generators

Being prepared for any power disturbances will ensure business continuity and workplace safety. Due to their input voltage window, Uninterruptible Power Supplies (UPS) can handle the reduction in voltage. When the mains voltage drops too far, the UPS batteries take over without any disturbance to the load. 

 

The same applies for when the voltage surges, a UPS transfers the load to batteries and won’t so as not to pass the surge onto the load. Depending on the severity, the UPS may sacrifice itself, absorbing the spike/surge to protect equipment such as servers from frying, ensure there is no data loss and protect against memory loss.   

 

UPS also provide instantaneous power in the event of a complete power failure/blackout, ensuring there is no drop in supply to business equipment.  

 

With additional strain expected to be placed on the mains power grid as global warming continues to change weather patterns and as the country changes to greener energy alternatives, it is becoming more important than ever to protect businesses from power problems. Contact Power Control for a free site survey.