Electricity blackouts are predicted to become more frequent as growing demand continues to reduce supply margins, but planning for shortfalls can lessen the impact.
The tsunami that devastated Japan's eastern coast may have faded from the headlines, but the impact continues. Damage to several of its nuclear power plants means that simply keeping the lights on has become a daily task for the operators.
However, Japan is not alone in suffering blackouts. Alaska, New Zealand, South Africa and Chile have lately been blighted by severe electricity shortfalls. The root causes of electricity shortfalls are numerous, ranging from shortages in the supply of raw materials for electricity generation through to shortcomings in generation, transmission and distribution.
The general consensus is that these shortfalls, leading to possible blackouts, are likely to increase as the power grid is transformed from the central generating model to a spider's web of local and renewable generation, with two-way flow all backed up by the traditional baseload generation. However, the best way to survive these shortfalls is to plan now.
'Prolonged electricity shortfalls can reduce economic competitiveness by creating uncertainty in electricity supply and increasing electricity costs,' Nobuo Tanaka, executive director of the International Energy Authority (IEA), says. 'Load shedding cost the Pakistani economy several billion dollars in 2007 alone. Power outages resulting from the 2009/10 electricity shortfall in Ethiopia led to an estimated gross domestic product (GDP) loss of 1.5 per cent.'
The environmental impacts of a prolonged electricity shortfall can also be significant. Faced with mandatory rationing or indiscriminate blackouts caused by load shedding, consumers often invest in expensive on-site electricity generation produced by air-polluting fuels.
However research from the IEA has suggested that many of the negative effects can be avoided, or at least minimised, with the application of proven energy saving strategies.
Over the past five years there have been serious disruptions to supply that have been met with a variety of emergency measures. Some have enjoyed great success that has led to long-term energy savings, others have enjoyed far less impact.
The most recent blackout occurred in Japan earlier this year after an earthquake and tsunami struck the east coast, forcing several large nuclear and thermal power stations out of service for an extended period. Over 27GW was estimated to be out of service and Tokyo Electric Power Co (TEPCO) was forced to implement rolling blackouts, at great economic and social cost. Improved weather in April, > < and the return of thermal plants to service, allowed a cessation in rolling blackouts.
However that was far from the end of the problem. To avoid blackouts that might arise as the summer peak caused demand to surpass supply, the government decided to implement an energy-saving strategy through a hastily assembled electricity supply/demand emergency response headquarters.
Officials faced an early challenge: a lack of sector-specific or end-use specific load data made it difficult to say which sectors could contribute the electricity savings needed to avoid blackouts. The government convened a group of researchers, officials and TEPCO staff to estimate load curves, predict energy-saving potential for each sector and develop recommendations for saving electricity.
For industry consuming more than 500kW, the government implemented Article 27 of the Electricity Business Act, which authorises the government to restrict electricity use. Between the hours of 0900 and 2000, players in this sector must cut electricity consumption by 15 per cent compared with the same period the previous year.
Juneau, Alaska, US, 2008
It is always a concern when a region has a high reliance on one particular generation source, and that fear was reinforced in Alaska three years ago. Over 90 per cent of electricity supply to Juneau, Alaska, comes from hydroelectric facilities located 60km from the city. When an avalanche severed Juneau's transmission link to its hydroelectric power supply, the utility switched immediately to reserve diesel generators. Diesel fuel supplied almost all of the city's demand until the line was repaired six weeks later.
At the time, diesel prices were at record levels and much higher than the cost of hydropower. As a result, the cost of generating a kilowatt-hour (kWh) of electricity delivered to customers rose from $0.11 before the avalanche to over $0.50.
Juneau's municipal government realised the only way to prevent skyrocketing electricity bills was to prompt consumers to cut consumption. The city led the way by switching off alternating streetlights, certain equipment and lights in public buildings.
With the city's approval, the Juneau Economic Development Council (JEDC) organised a city-wide energy-saving campaign. The information campaign, called 'Juneau Unplugged', provided end-users with advice on how to quickly and safely conserve electricity.
The impact of the campaign exceeded expectations. Juneau's electricity consumption fell more than 40 per cent in six weeks, from about 1,000MWh a day prior to the avalanche to less than 600MWh.
Electricity shortfalls continue to plague many countries. In the past decade nearly every part of the world has been hit by an electricity shortfall and resulting power interruptions. It is expected that these will continue as political, regulatory and financial hurdles make it difficult for government and energy utilities to invest the estimated $16.6tn that will be required to meet the predicted annual growth in demand of 2 per cent.
'Developing emergency demand-side energy-saving programmes as insurance against delays in supply additions may be an effective strategy for many governments to consider,' says Tanaka. 'No country is immune to electricity shortfalls: they can occur anytime and be caused by many factors. However, the economic and social impacts of such shortfalls can be minimised by implementing carefully planned emergency energy-saving programmes.
'Governments should lay the foundation work for emergency energy-saving strategies well before a crisis arises.'
Any strategy should consider what kinds of electricity shortfalls are most likely in that particular region. If power plants are located on fault lines or tsunami-prone areas (Japan), transmission lines run through avalanche zones (Alaska) or demand growth exceeds supply investments (South Africa – see box, right), leaders should consider scenarios in which capacity constraints lead to electricity shortfalls during peak electricity-demand hours. In these situations, measures should aim to cut electricity demand during specific times of the day. *