In the early days, electricity was generated mainly by simple mechanical methods that turned dynamos or generators. The principle was discovered in the 1830s by Michael Faraday, who showed that moving a magnet near a coil of wire could produce an electric current.

The earliest electricity supplies were very local. A factory, mill, large house, or street lighting scheme would often have its own generator.

Here are the main early methods:

1. Steam engines

By the late 1800s, most electricity was produced by steam engines. Coal was burned to boil water into steam, and the steam drove a piston engine or later a steam turbine connected to a dynamo.

Typical uses:

• Street lighting
• Tramways
• Factories
• Wealthy homes
• Public buildings

Early power stations were small and local because electricity could not easily be transmitted long distances.

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2. Water power

Some early electricity generation used water wheels or water turbines, especially in rural areas and mountainous districts. Existing mill streams were adapted to drive generators.

This was one of the first forms of hydroelectricity.

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3. Gas engines

Before large national systems existed, some towns and businesses used gas engines fuelled by “town gas” made from coal. These engines drove small generators.

4. Wind and small local systems

A few isolated farms and estates used small wind generators or private battery systems, especially before rural electrification.

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5. Direct current (DC)

The first systems usually used direct current, associated with Thomas Edison. DC worked for nearby lighting but could not travel far efficiently.

Later, alternating current (AC), promoted by Nikola Tesla and George Westinghouse, allowed electricity to be transmitted over much greater distances. That led eventually to large national grids.

In Britain, one of the earliest public power stations was the Holborn Viaduct power station in London in the 1880s. At first, electricity was mainly for lighting rather than for the huge range of appliances we use today.

The interesting point is that early electricity was often highly localised. Many places generated only what they immediately needed. The later national grid system came after engineers learned how to interconnect many power stations and transmit electricity over long distances.

For many years Britain has assumed that the future of electricity would simply involve “more of the same” – more power stations, more cables, more electric vehicles, more heat pumps and more dependence upon a huge National Grid carrying electricity across the entire country.

But there is growing evidence that this assumption may be impossible.

The National Grid was developed during the age of industrial growth when energy was abundant, industry was expanding and the economy was becoming larger every decade. The entire system was designed around centralisation. Huge power stations generated electricity in one place and transmitted it over long distances to passive consumers.

The new vision is entirely different. Millions of houses are expected to charge electric cars, run heat pumps, install batteries and sometimes even feed electricity back into the system. Instead of a relatively stable flow of electricity from large generators, the Grid is expected to cope with countless small and fluctuating inputs and demands.

At the same time Britain is attempting to close older reliable generation systems while becoming increasingly dependent upon intermittent wind and solar generation. Electricity may be plentiful one day and scarce the next. The balancing of the system becomes extraordinarily difficult.

The problem is not simply generation. It is transmission.

Electricity grids are physical systems with limits. Substations, transformers and cables can only carry a certain load. Much of Britain’s electricity infrastructure was never designed for simultaneous vehicle charging, electric heating and battery storage on a national scale.

Upgrading the entire system would require enormous quantities of money, raw materials, engineering labour and time. In a shrinking economy these become increasingly difficult to obtain.

The contradiction is obvious. Britain is attempting to build an electricity-intensive society precisely at the moment when economic surplus is beginning to contract.

Even if the technology works technically, the affordability becomes doubtful. Households already struggle with energy bills. Councils are close to insolvency. Government debt rises continuously. Large infrastructure schemes become more expensive every year.

There is also a deeper structural problem. Centralised systems become fragile when complexity increases beyond a certain point. A fault in one area can cascade across the entire system. The larger and more interconnected the network becomes, the more vulnerable it may become to instability, cyber attack, equipment shortages or financial failure.

This may eventually force a historic reversal.

Instead of ever greater national integration, electricity generation may increasingly become local.

Localities may begin generating much of their own electricity through combinations of small-scale solar, micro-hydro, local wind generation, biomass, methane digestion and small community battery systems. Essential activities could then be organised around the actual electricity available locally rather than around the assumption of unlimited supply.

A localist electricity system would not attempt to maintain the present consumer society in its current form. That may no longer be possible. Instead it would concentrate upon resilience and essential needs.

Food production, water pumping, refrigeration, workshops, local transport and basic communications might become the priorities. Electricity-intensive discretionary activities may gradually decline because the energy surplus to sustain them no longer exists.

Large national systems may still survive for essential strategic purposes, railways, hospitals, heavy industry and national communications. But the assumption that every locality can indefinitely depend upon an endlessly expanding national electricity network may prove unrealistic.

In many ways the future may resemble the past more than the present.

Before national grids existed, localities often generated power locally through water mills, small gas works and local electricity plants. The future may involve a more technologically advanced version of the same principle.

The great irony is that the modern drive toward electrification may ultimately undermine the very centralised grid system upon which it depends.