Electricity Supply From Refuse Dump

It was very sad to read from the official website of the Federal Ministry of Power that peak generation in Nigeria declined to barely 3,200 MW compared to forecasted peak demand of 12,800 MW. The implication is that 75 per cent of consumers’ electricity requirement will go unmet, resulting in rolling blackouts! This is inexcusable and unacceptable. There is the need to explore alternative sustainable energy solutions to meet the challenge, consolidate ongoing initiatives, and fast-track development. A case in point is integrated waste management and energy supply schemes. This seemingly uninviting industry has the capability to create new and vibrant markets, attract direct private investment, open new jobs opportunities and contribute to realise our national sustainable development targets.

Currently, waste management authorities in Nigeria collect and dispose municipal solid waste mainly to landfills and dumps. This open-dumping approach pollutes the environment, renders habitable land useless, and impacts air and water quality. Nigeria could take advantage of the opportunities in converting waste-to-electricity (WTE). This WTE technology is well known and there exists several projects of its kind worldwide.

Today, the Edmonton incinerator in London, the United Kingdom, inaugurated in 1974, burns approximately 600,000 tonnes of municipal solid waste annually to generate 55 MW of electricity, enough to power 24,000 households. According to information available from the Lagos Waste Management Authority, approximately 3.5 million tonnes of waste is generated annually in Lagos. This could potentially generate up to 320 MW of electricity, which accounts for roughly 10 per cent of the current national peak generation and about 35 per cent of the peak demand of Lagos State. Interestingly, this simplified analysis can be adapted to estimate the waste-to-electricity potential of the 36 states of the federation.

The process of converting waste to electricity can be easily explained. First, the waste is mixed to achieve homogeneity and incinerated in a combustion chamber at temperatures up to 1,200°C. Next, the resulting heat is used to boil water to produce steam. This high pressure steam is used to drive steam turbines to generate electricity which could be utilised locally or injected into the national grid.

As solid waste is a necessary by-product of civilisation, the security of feedstock for the WTE plants is assured, unlike existing hydro and gas plants which suffer from reduced water levels and disruptions on gas transit pipelines. Moreover, the bottom ash and ferrous metals derived from the combustion process can be used for road construction and recycled in steel rolling mills.

On the other hand, biogas can be synthesised from food and animal waste using the process of anaerobic digestion. This biogas can be utilised for domestic cooking and/or combusted in a gas turbine to generate electricity. In this manner, the waste from fruit markets in our cities could directly provide electricity to the stalls and environs. Moreover, it is estimated that the daily muck from two cattle or six pigs could produce enough biogas to meet the cooking requirements of a household. This will reduce dependence on unclean and expensive cooking fuels such as kerosene and firewood. This clean cooking solution will reduce indoor air pollution, which accounts for one death every nine second globally, according to the World Bank.

How to connect the dots between these lofty solutions and extant realities? There is the need to carefully think about innovative business models for the WTE market. It must be driven by public-private partnership. It will be right for government to use public derisking instruments such as political risk insurance to reduce risks that investors face and leverage private investment. This way, investors will gain the confidence and trust to build, operate and transfer the power generation infrastructure under predictable, stable and viable economic arrangements. The result will inspire a wide range of skilled and unskilled jobs across the value chain.

Another missing piece of this waste-to-energy jigsaw puzzle is the requirement for training and human capacity development. Mindful of the inadequate performance of our technical colleges, new training arrangements must be explored. It is my opinion that government should prioritise investment in state-of-the art ‘training parks’ fitted with modern communication facilities, with reliable internet access, and uninterrupted power supply wherein world class training firms could take up space to organise half-day to week-long training for early stage professionals and refresher courses for experts. Furthermore, local government authorities must engage and consult with domestic and industrial waste producers to reform waste management policies.

True, the electricity mix will be composed of a wide range of energy sources to realise our ambitious sustainable development targets. However, our national energy future must focus on progressive shift away from fossil-based sources to renewable solutions such as waste-to-energy. The thrust for this transition must be driven by robust public-private partnerships. The three tiers of government must firstly synergise plans to use public financing instruments to reduce risk faced by private investors. Training facilities must be established in partnership with private investors to train young apprentices and early-stage professionals. Local government authorities must shape up to deliver integrated waste management schemes that will enlighten communities, create new jobs, and enhance continuity of feedstock supply to generation companies. This way, we will dispel darkness and restore light!

Source:punchng.com