Energy Demand and Supply Reliability

Effects of an Energy Supply Failure

An energy supply must be available when people need it and reach the places where it is used. Cost and environmental effects also matter. If the supply fails, lighting, water pumps, medical devices, food cooling, and communication networks can stop working.

Electricity powers many devices used each day. It is an energy carrier produced using fuels, water, wind, sunlight, or geothermal heat.

Electricity reaches users through several connected stages.

Energy starts at a source and is converted into electricity. The grid then carries it to the user.

Generators must supply enough power, and the grid must deliver it when demand rises.

Demand Adds Up across Many Devices

One lamp may look simple. However, energy demand becomes large when many devices are used by many people at the same time.

For an electrical device, energy use is calculated from power and usage time.

Symbol notes:

Suppose $5$ lamps, each with power $10 \text{ W}$, are turned on for $4 \text{ h}$. The energy used is:

The value $0.2 \text{ kWh}$ covers only five lamps. The same pattern across many homes, schools, clinics, and small businesses produces much larger total demand.

Peak load occurs when many devices use electricity at the same time, so the grid must provide more power during that period. Two areas may use similar daily energy, but the area where many devices turn on during the same hour needs more grid capacity at that time.

National Rates and Local Access Gaps

Electrification Ratio is the percentage of households with access to electricity. Electrified Village Ratio is the percentage of villages or urban villages that already have electricity.

In the fourth quarter of $2024$, Indonesia's Electrification Ratio reached $99.83\%$ and its Electrified Village Ratio reached $99.92\%$. However, $5{,}821$ villages or urban villages still lacked electricity access from PT PLN (Persero).

National ratios need local context. The remaining unserved locations may be difficult to reach, scattered, or far from the main grid even when the national percentage is very high.

Rising Demand Requires More System Capacity

Global electricity demand is forecast to grow by an average of $3.6\%$ per year from $2026$ to $2030$. The main drivers are industry, electric vehicles, air conditioning, and data centres.

Electricity demand can rise because more energy is needed for education, health care, food production, transportation, and businesses. The risk appears when supply and grids cannot keep up, which can lead to blackouts, higher costs, or heavier use of more polluting energy sources.

Daily energy demand and peak power are different requirements. A system may supply enough energy over a full day and still fail when many devices run at the same time. Generation, the grid, or storage must therefore cover both total energy use and the highest simultaneous power demand.

Questions for Assessing Energy Needs

Do not assess an energy-demand figure on its own. Also check who needs the energy, when it is needed, how much energy and power are required, which source is used, whether the grid is ready, and what happens if supply fails.

If the daily supply is too small, total energy is the problem. If many devices run at once, peak power may be the problem. The other questions check whether the source, grid, or storage is limiting supply and what will happen if supply fails.

Match Renewable Sources to Site Conditions

A renewable-energy source suits a location when the local resource, technology, network, storage, and environmental safeguards can meet local needs. The table lists the first checks for several resources.

The energy system therefore needs to match local demand, environmental conditions, and community needs.