Nossos dois grandes projetos de pesquisa anuais estão em fase de conclusão: tanto a nossa Pesquisa Global de Tarifas da Água como nosso inventário de usinas de dessalinização serão publicados no próximo mês.
As duas questões que abordam – o preço da água e a resposta à escassez – vêm gradualmente se unindo ao longo dos anos. Este ano, elas foram discutidas na Cidade do Cabo de tal forma que tivemos que repensar completamente nossa publicação de dessalinização.
A cidade sul-africana enfrentou uma seca que se comparou com a seca do Milênio na Austrália em termos de gravidade, mas a resposta da cidade foi muito diferente. Não se apressou em comprar grandes usinas de dessalinização como uma apólice de seguro contra futuras carências. Em grande parte, enfrentou a crise através da gestão da demanda. A prefeitura introduziu tarifas punitivas à seca que elevaram o preço da água de US $ 2,00 / m3 (para aqueles que consomem menos de 6m3 / mês) para US $ 61,00 / m3 para aqueles que usam mais de 35m3 / mês. No geral, a demanda por água na cidade caiu de 180 l / c / d para 110 l / c / d, e as barragens estão sendo reabastecidas. As usinas de dessalinização temporária de pequena escala que a cidade havia encomendado, apenas no caso, começaram a parecer irrelevantes.
Desalination still has an important place in the future of Cape Town’s water supply. Not least because the population is growing, and as it becomes more wealthy, more people will have access to thirsty domestic appliances such as showers, washing machines, and eventually swimming pools. The city needs to develop new long-term water resources, but these include water reuse and other measures to improve water efficiency – as well as desalination.
It is a different proposition to the 24/7 scarcity markets of the Middle East. In that region, governments are happy to buy as much desalination capacity as they think they need. They know what it is all about, and the risk of building something they don’t need is pretty low.
Outside the Middle East, it has undoubtedly become more difficult to sell desalination as a solution to drought since the Australian experience. Cape Town’s successes with demand management will magnify that trend, but that should not mean less long-term demand for desalination. The real market for desalination is not in droughts, nor even in scarcity – it is in water security.
Water security is a larger market than just desalination: it includes water reuse and leakage reduction, as well as conservation and demand management. It is about giving the population of a city the confidence that water is never going to limit their future aspirations. Desalination has something unique to offer this market: it is often the lowest cost drought-proof directly potable additional water resource available. However, outside the 24/7 desalination markets it is important that the industry adapts its mindset from selling desal plants to selling water security, and lets desal take its place alongside other potential solutions.
We are doing our bit by refocusing and rebranding the IDA Desalination Yearbook. For the past 11 years we have published this on the basis of an annual update of our desalination plant inventory, co-branded with the International Desalination Association. This year we are expanding it to include a listing of all the new water reuse plants built around the world, as well as a record of “smart” water efficiency projects. It is being renamed the IDA Water Security Handbook. We hope that it will become a resource for any public authority or industrial water user looking for technological solutions to guarantee their water security. We will be launching a companion website later this year.