Around the world, renewable electricity generation by solar and wind is increasing at exponential rates with shares approaching 50% or more in some countries. New ways to manage energy generation, transmission, distribution, and storage are being established, as well as how to best manage the integration of new renewable electricity with traditional, centralized energy sources, such as coal, gas and nuclear power plants. Please use the slide show or read the content below to understand how certain myths regarding the impact of large amounts of renewable energy added into the grid are being dispelled.
Wind and solar will never replace baseload generation, the constant electricity production typically provided by coal, nuclear and large hydro power plants.
Wind and solar already provide periods of 100% renewable electricity coverage in countries such as Denmark, Germany, and in parts of Australia.
In the future the importance of baseload will decrease as grids transform to having primarily variable generation supported by flexible and on-demand sources, such as energy storage. Strengthened interconnections, smart grid technologies, and load management strategies enable greater efficiency and better control, which in turn creates flexible, reliable, and economical renewable based power systems.
Wind and solar are too intermittent for reliable grid operations and cannot be predicted.
Wind and solar forecast predictions are increasing in accuracy, in team periods from minutes to several days. These forecasts provide grid operators with information about what the power output of renewable power plants will be to a high degree of certainty.
This information then allows the operators to anticipate how to best control fluctuating loads with other flexible power sources to match energy supply to its demand. It also promotes demand side management, which are initiatives and technologies that encourage consumers to optimize their energy use.
Expensive storage is required to further increase reliability and renewable energy use int eh electricity grid.
A minimum of storage in the form of batteries, hydrogen, and pumped hydroelectricity will certainly support increased renewable energy integration and help prevent costly energy waste. However, increased grid flexibility and management, interconnections between regional grids, and dispatch able power sources, like on-site combined heat and power (CHP), allow for greater renewable energy integration even without storage while increasing power supply reliability.
High quantities of wind and solar energy will destabilize the grid and cause blackouts.
Knowledge is power. The key is to install and manage smart systems that allow a smooth integration and control of variable electricity sources. This way grid operators can ensure that sufficient electricity is supplied at all times, resulting in a more resilient grid. For example, the average blackout duration was cut in half in Germany after the integration of 40% renewable electricity.
For every PV or wind power plant, an equal capacity of fossil fuel generated electricity must be running in the background, negating most of the carbon emissions benefit.
Renewable energy and storage systems combined with other modern grid-management tools can reduce the number of operating fossil fuel power plants the must be run in the background, known as “spinning reserves”. This reduces net grid carbon emissions.
The need for additional fossil-based power plants that can raise their output to replace renewable sources when the wind drops or clouds pass overhead will be minimal as the grid becomes more flexible and “smarter”. Several grids, for example in Tasmania, Uruguay and Costa Rica, already operate for periods of hours to day s on 100% renewable electricity with no additional fossil fuel power plants running in the background, only requiring a small spinning reserve for any power generation, regardless of its source.
The duck curve, which shows a late afternoon load spike as large amounts of solar energy go offline coincidentally during the evening peak electricity demand, will be very difficult and expensive to solve.
Increased demand side management coupled with short-term balancing and electrical storage (possibly making use of electric vehicles adjusting their charging practices) can solve this problem without causing instability in the grid. This is already being explored by some grid operators by promoting “Time-of-day” pricing that encourages greater electricity use during the off-peak early-morning, mid-afternoon, and night-time hours.
Excess renewable energy generation will be wasted, causing retail electricity prices to increase.
There are many ways to utilize excess generation to provide3 additional benefits, including power-to-heat, (e.g. heat pump operation for district heating), pumped hydro storage, and hydrogen or synthetic fuel production. Not only does this create other valuable products, but it can also increase grid stability. In regions with interconnections, excess renewable energy can be exported to supply low emission electricity in adjoining territories, also increasing revenue.
Transmitting renewable energy across the electricity grid over long distances is highly inefficient and costly.
Renewable energy generation can be very local in nature. Solar PV systems, in particular rooftop solar, are located close to consumers, effectively reducing transmission grid requirements.
For long-distance power transmission from large PV and wind plants in optimum resource regions, new high voltage direct current (HVDC) transmission lines are efficient and allow for electricity exchange over whole continents, increasing grid stability and renewable energy use.