Daniel Howcroft, Liverpool John Moores University, discusses the need for improved lightning prediction systems.
Lightning is a complex and fascinating natural electrical phenomenon, extremely destructive and little understood by most. Recent research shows that it could have even started life on Earth, by striking the primordial ooze that covered the surface and altering the molecular makeup of certain compounds.
Lightning is caused by the transfer of electrons from a negatively charged cumulonimbus cloud to the positively charged Earth’s surface, or occasionally vice versa. Contrary to popular belief, lightning does indeed strike twice. The lightning flash is made up of one or more lightning strokes, where a stroke is the transfer of current. A typical lightning discharge is approximately five times hotter than the surface of the Sun, and each carries tens of thousands of amps. This means bad news for the thousands of electrical assets and the hundreds of kilometres of exposed cables. Although spectacular to watch, an unfortunate lightning strike to an under protected overhead conductor or substation is capable of causing millions of pounds in damage, blackouts and even death.
Currently the best way to protect assets is to use a lightning rod or air terminator. But what if your assets were human? Although the number of deaths per year is falling, it still remains a very real threat. Every day maintenance workers expose themselves to harsh environments, to ensure we get an uninterrupted supply of electricity. So how do we keep them informed of an approaching storm? Companies such as EA Technology regularly warn maintenance crews of approaching storms by pinpointing individual strikes using their cutting-edge lightning location service. Being able to predict a storm hours before they happen will give maintenance crews more time to clear potential hazards, allow control engineers to shut down vulnerable assets and ensure adequate protection is in place, and facilitate better planning of maintenance tasks.
This would ultimately save lives, time and money. With climate change causing freak weather patterns, the need for a cheap and reliable lightning prediction system is ever increasing. But what if we could accurately predict the location and time of a lightning strike before it has even reached the ground? If we could detect the build-up of the negative charge in the clouds, this could give an indication as to the likelihood of a storm. If we then had the capability to predict where lightning would strike, could we make man’s dream of harnessing the power of lightning a reality? Could we add another source of renewable energy to the list, and turn this dangerous nuisance into a helpful, usable commodity?