Wind and solar power are now considered the main source of electricity. But that was not always the case – only 15 years ago, they were considered expensive. But are wind and solar PV all we have? The answer is no. There are various other technologies, today we want to introduce ocean thermal energy conversion, which is called OTEC. In a recent study in Indonesia, we showed that not only this source of energy has great potential, but it can also be cheap-Power to Choose .
Indonesian islands are rich in plants and non-fossil energy sources. But people live in it to a certain extent. For example, more people live on the island of Java alone than in all of Russia. The economy is growing rapidly and is expected to be the fourth largest in the world within a few decades. Electricity consumption is expected to increase by 5% per year over the next few decades – where is all this supposed to come from? OTEC can be one of the main options.
What is OTEC?
Energy is produced by the temperature difference between the warm surface of the ocean and the cold layer. The temperature at the bottom of the ocean is a few degrees below zero. Efficiency and cost considerations require the temperature to be higher than 24 ° C. This limits the application in the tropical and subtropical regions of the Earth. But perhaps no country has such high potential as Indonesia.
With the help of the local information system, we investigated all possible locations for OTEC in Indonesia. Some areas should be excluded because the sea is not very deep, and the deep water of the sea cannot be reached. Natural preservatives are also avoided. This leaves us with 1,700 sites where OTEC plants of up to 100MW can be installed. Finally, a financial analysis was conducted for each site. The price depends on many factors, of which the temperature above and the distance to the shore are important. These costs are compared to local electricity prices; This varies greatly across Indonesia, with prices ranging from around ȼ6 per kWh in areas such as Java and Bali to over ȼ15 per kWh in rural areas. Then we created an initial presentation, starting with the best OTEC site, and then choosing the best site. We also considered learning technology, that is, the effect of reducing electricity costs by increasing installed capacity. It turns out that this learning effect eliminates the effect of less efficient areas, that is, the cost of producing electricity can decrease over time:
The big question remains: how to get there?
OTEC is a proven technology, but only in an accelerated form: the largest plant currently operating is 100 kW in Hawaii, and the largest plants in planning are 10 MW in size. Even if the duration of the benefits exceeds the costs, the initial investment is very important: billions of US dollars will be invested over 20 years.
For wind and solar energy, we have come a long way, and it is high-income countries such as Germany, Japan, the United States, and Spain that have taken the lead and supported many of the financial burdens to bring these technologies to the mainstream.
What they are today:
Often among the cheapest sources of electricity. OTEC seems to be a suitable source of electricity in Indonesia, and possibly in countries such as Brazil, Sri Lanka, Madagascar, parts of India, and the Caribbean region. But none of these countries have a lot of money, and the question is who will bear the burden of money in this case. It seems appropriate that organizations such as the World Bank and the Green Climate Fund play a leading role. Also, it seems that it would be wise to use the climate funds of developed countries to commit themselves to the process of climate negotiations.