Tripping the light fantastic

"This might make you jump a bit," warns Ian Cotton.

It is near pitch-black in the viewing room where we are standing; a soft red glow exuding from a warning light above the door barely cuts through the darkness.

Every day, millions of volts of electricity pass through the National Grid High Voltage Laboratory at the University of Manchester.

The hangar-like facility is packed with enormous pieces of equipment: transformers, generators and the odd huge aluminium sphere stand tall. A glass-fronted viewing room, where experiments can be safely watched, is adjacent.

It is one of the few places in the UK where scientists can work with huge voltages at first-hand.

Lightning tests

Ian Cotton, a senior lecturer at the University of Manchester's School of Electrical and Electronic Engineering, says: "We do a lot of lightning protection work here."

Electricity is taken straight from the mains, at the UK's standard 240 volts, but a towering impulse generator then ramps it up to a massive two million volts - creating a voltage that can be used to see how lightning attaches to objects.

But, according to Dr Cotton, this has a drawback: "If lightning hits [glass fibre], it would blow apart and incinerate - and you cannot have that on a plane.

"This means that they have to have special lightning protection - diverter strips that are often made from segmented pieces of metal.

"And we are able to test how well they can guide the lightning to a safe place in a lab like this."

Now the blades have a protection system built in, which is especially important as wind turbines can be placed offshore where repair is difficult.

Dr Cotton says: "We are constantly checking that these lightning protection systems work well and we are working on improving their resistance to lightning."

Buzzing power lines

This one boosts electricity to 800,000 volts - about double the voltage that power lines or substations carry.

"We use this generator to carry out experiments on all of the types of equipment that are used on the power system," Dr Cotton says.

"If you own lots of overhead lines and cables, you want to understand how they are working and when they will fail."

Of particular interest are insulators - the devices that resist the flow of electrical current to make electrical apparatus safe. You normally see these carrying the conductors on an overhead line.

The team feeds them with electricity to investigate where and when any strains and weaknesses appear.

In the lab, when the voltage is turned up, the insulators turn a gentle shade of blue as corona discharge - the buzzing noise you sometimes hear around power lines - begins to emit.

They then begin to spark violently as they reach the point at which an electrical breakdown occurs.

Ageing equipment

A decade after this life limit, some have expressed concerns of an impending electricity crisis should any equipment begin to fail.

However, regular tests carried out at this facility, and at other similar labs around the country, show that the equipment is continuing to function well and shows little decay.

Dr Cotton says: "The problem is, when a lot of this new kit was designed, no-one really knew how to predict its lifespan - 40 years was a pretty arbitrary number."

He adds that it is important to keep on testing the apparatus, a process known as condition monitoring - and this is really where high voltage labs come into their own.

He explains: "Electricity is important in our everyday lives; now people take it for granted - you switch on a light and you don't really think about how it gets from a power station to your house.

"But that process is a complex path of overhead lines, cables and substations, and all of them have to be working well virtually all of the time.

"You cannot make anything 100% perfect, but the better you can make it, the more chances you have of keeping the lights on."

We hope this researche find electricity source and applied as cheap and safe energy.