What does this method involve?
Where the sun can energize photovoltaic panels for a handful of hours a day and the wind can blow turbines for days on end, but also disappear for extended periods without warning, the tide i waves are almost constant. This endless movement of waves, currents and tides can be used to produce clean, renewable electricity.
To produce energy from waves and tides, there are different types of technologies, for example: buoys (structures that move up and down with the movement of the waves), or oscillating water columns (motion processing “in” and “out” of the water coming in. the columns). Once the electricity has been produced by wave or tidal energy devices, it can be transported via a submarine cable or stored in special batteries.
Emissions and cost impacts
This electrification technology has a much lower level of maturity than those analyzed before.
The issue has been raised and is being studied to power offshore oil and gas platforms, but today no one is making real use of this technology, although case studies show “promising results”.
Hypothetically, each kWh of energy generated by waves or tides saves around 1,000 g of CO2 compared to the same power generated by dieselin addition to reductions in the emission of all other types of greenhouse gases such as methane (CH4) and nitrous oxide (N2O). Wave and tidal energy has one of the lowest carbon footprints of all energy types. Based on the life cycle, tidal energy emits less than 22 gCO2.
As for the costs, there is limited data to draw concrete figures. Examining existing tidal or wave energy projects can help provide financial guidance on upfront and maintenance costs. In general, generating electricity from tsunamis and waves costs 2 to 9 times more than the maximum average price of wind power. In fact, wave turbines must be more durable than wind turbines to withstand ocean currents. According to a US Department of Energy estimate, tidal power costs between $130 and $280 per megawatt-hour (MWh), while wind power can cost as little as $20 per MWh.
Today, the costs of wave and tidal energy are generally very high because they are in the research phase and are usually paid for by government or research grants. There are no energy companies using wave energy at scale, which would lower costs. These plants are expected to be expensive to maintain because they are submerged in constantly moving salt water. In addition, wave energy plants will likely require regular (and expensive) maintenance.
In addition to high costs, one of the biggest drawbacks of wave and tidal energy projects is that no utility company currently has the capacity to install wave farms because they are not yet large enough to provide a significant amount of electricity. While some wave energy systems have been tested in Scotland, Hawaii and, more recently, Australia, their power generation capacity is only about 2.5 MW at maximum. The industry is expected to grow, but implementing wave energy generators on a usable scale remains a challenge.
Finally, precautions must be taken to avoid unwanted effects on the environment. For example, these devices can disrupt ocean currents, altering the natural patterns of food and larvae. Also, if the turbines produce noise, it can disorient marine animals, causing them to collide with nearby equipment or land. Early research has shown that fish and marine mammals can avoid hitting the devices, but sometimes they don’t. It is important that scientists continue to investigate how local plants and animals respond to these devices.
This method is still very prospective, and not concretely applied today, but it is an interesting avenue to explore in the future.
