Rural health worker Patrick Kamzitu is relaxed about the long and frequent power cuts that plague Malawi and which last week almost brought it to a halt when the whole country went dark for two hours.

“Power cuts? We have no power cuts here. We hear of what is happening in the cities but we have no problem here because we don’t have any electricity to cut,” he says.

Nambuma, a small town 50km over dirt tracks north-west of the capital Lilongwe, was promised mains power by the government five years ago. But although there are new poles lying on the side of the road five miles away in Ngoni, the electricity has still not come.

Like almost 90% of Malawians, the 12,000 people living in the Nambuma area are resigned to never being able to switch on the lights.

But patience is wearing thin for the 10% of Malawian households that are connected to the grid and are supplied by the state-owned Electricity Supply Corporation of Malawi (Escom) or the private Electricity Generation Company.

Prices have risen sharply, and daily rationing and lengthy “outages” lasting from a few hours to several weeks, depending on where people live, are now the norm. A familiar sound in Lilongwe, Blantyre and Mzuzu, the country’s three urban centres, is of diesel generators kicking in as the lights flicker and go out.

People are long used to shrugging and accepting the cuts, but anger boiled over at last week’s national blackout. Irate MPs were forced to use their mobile phones to read in parliament, businesses complained about having to burn expensive diesel and there were threats of demonstrations.

Escom was forced to make a rare public apology, blaming the national blackout on a fault on the power line between two of the country’s largest hydroelectric plants.

“There are people’s lives concerned here. We have cases of premature babies dying in hospitals due to the absence of power for the incubators. This is unacceptable,” says Dorothy Ngoma, president of the National Organisation of Nurses and Midwives of Malawi.

The usual explanation for power cuts in December is that it’s the end of the dry season, when water levels in Lake Malawi and the Shire river, which together feed the country’s largest hydroelectricity plants, are at their lowest. In the past three weeks hydroelectric output has been halved, a figure worsened by the two-year drought brought on by El Niño, which has left lake levels at historically low levels.

New back-up diesel generators, hydro and solar plants are due to be installed shortly which should improve the situation in 2018, say the power companies, but they warn that people must be patient. “Malawi will continue to experience power cuts unless the country receives above normal rainfall for five consecutive years,” says Escom’s former CEO Evelyn Mwapasa.

But it will be decades before every household gets connected. Malawi has the capacity to generate just 300MW, which is little more than a single Scottish wind farm; and even without a creaking infrastructure its power companies cannot keep up with soaring demand from a fast growing population and fuel-hungry companies needing electricity for computers and manufacturing.

“The country faces a widening gap between electricity demand and supply, which is being exacerbated by urbanisation, economic development and population growth,” says John Taulo, deputy director of the Malawi industrial research and technology development centre in Blantyre.

Grid coverage is growing slowly but demand is doubling every 10 years or so. “[We are] faced with serious energy supply problems, including rising energy and electricity demand; insufficient power generation capacity; increasingly high oil import bills; lack of investment in new power generation units; high transmission and distribution costs, transmission losses; poor power quality and reliability,” he says.

No electricity means no development but also widespread environmental degradation, according to the UN development programme. Nearly 75% of Malawian households depend on charcoal and wood burning for cooking, and coal and fossil fuel imports have grown, it says.

Charcoal production is now big business, with people carrying it many miles to sell in cities. Aside from the indoor health impact of burning wood to cook, deforestation also leads to soil erosion, which, in a vicious circle, silts up the rivers and blocks the hydroelectricity plants.

The power cuts keep the country poor and hungry, says the World Bank, which calculates that electricity rationing loses Malawi up to 7% of its GDP a year. This is more than any other country in Africa. In comparison, Kenya, Niger, Madagascar and Benin all lose under 2%.

There is a strong link between human development and per capita electricity consumption, say researchers. Malawi has one of the world’s lowest electricity consumption levels and its human development index, of 0.418, is far below even the sub-Saharan regional average, ranking 170 out of 187 countries in the world.

Massive investment is needed if it and many other sub-Saharan African countries are to generate electricity and meet their development goals, says Mac Cosgrove-Davies, the World Bank’s global lead for energy access.

At a meeting last week in Abuja, Nigeria he said: “One billion people have no access to electricity, and six out of 10 of them, or 600 million people, are in Africa. Thirty-six countries have an electricity crisis.”

Cosgrove-Davies says it will need a 500% increase in investment over the next decade to meet sustainable development goal (SDG) seven, which calls on all countries to provide “access to affordable, reliable, sustainable and modern energy”.

Yet Malawi, like most of sub-Saharan Africa, has huge natural resources, which if tapped should be able to provide electricity for all. Solar electricity could cover 50% of the country’s power needs in a short time, and hydropower could be greatly increased.

A family in Wimbe, central Malawi, on a remote farm powered by a series of windmills and solar panels. Photograph: Lucas Oleniuk/Getty Images

The best hope, say government ministers, is multilateral banks working with private investors. The World Bank, Power Africa, the EU, the Shell Foundation, the UK government and the international Solar Alliance have agreed to help develop renewable energy across Malawi and other power-poor African countries. Malawi has been told it could apply for $500m (£375m).

Optimism is high. Connecting Malawi’s many thousands of villages to centrally produced power plants via a national grid used to be seen as the only option. Now it’s seen to be unrealistic and too costly. Instead, renewable energy is becoming much cheaper and easier to install. Micro-grids, which see whole villages being provided with solar or wind power, independent of the grid, offer another energy future.

But back in Nambuma, people are not waiting for the grid to arrive, says Kamzitu. “Solar is now seen as the way forward. People want power, now,” he says.

“Only 50 households have generators, but over 200 families have installed solar. They see it as more reliable and it’s easy and cheap to charge up. And they don’t have power cuts.”

