In-Depth Scenario Analysis Identifies Key Drivers Shaping Solar and Wind Energy Transitions Up to 2050
There are many systems involved in determining the makeup of the energy system, making it difficult to anticipate which factors are most likely to result in a particular mix in the future. This results in the currently available projections of future energy shares being highly uncertain. Wind and solar differ from other electricity sources in that their availability over hours or days is intermittent and cannot be controlled by electricity system operators. Although their availability can be predicted, uncertainty remains. Consequently, wind and solar deployment bring additional interactions and challenges to electricity supply and demand systems that require additional focus. We used the Global Change Analysis Model (GCAM) which represents a variety of the different systems involved (including energy, agriculture, land use, and water) to create a set of nearly 4,000 unique scenarios that span a wide range of possible futures. Each scenario is driven by a combination of different parameter inputs chosen based on factors that we expect will impact the relative contribution of different technologies in providing energy. By analyzing this set of scenarios, we can find the drivers, and combinations of drivers, that are important globally and in each of the 32 different regions represented in our model. We look at the scenarios that produced the highest fractions of wind and solar energy and identify four different pathways that can lead to these high renewable fractions. For each of the four paths, we explore how the implications for water consumption, air pollution, and food prices differ and result in tradeoffs.
Human decisions centered primarily on one sector, such as energy infrastructure, can have far reaching consequences for other sectors, such as land and water, and even on other regions, but analysis of those decisions is complex. The adoption of renewable energy is expected to be an important factor in many future scenarios, and solar and wind energy make up a significant fraction of the energy portfolio in many of these scenarios. However, both the future share of electricity generated by wind and solar and the pathways to adoption of these sources remain highly uncertain.
One of many reasons for this uncertainty is that multiple systems are involved in these questions. In particular, the energy, water, and land sectors are deeply interconnected, and, due to trade, sectoral changes in one region have the potential to impact other regions. By using a multisectoral model like GCAM in a large exploratory modeling exercise, we identified four different multisectoral futures that are all characterized by high renewable adoption but feature very different consequences across other sectors and regions. Many traditional modeling approaches would miss some portion of these potential futures.
The future capacity mix of the energy sector is highly uncertain, and consequences of different mixes occur across regions as well as other sectors. Using a multisectoral model like GCAM and completing a large ensemble exploratory exercise, we identified four different pathways to a capacity mix with high renewables adoption. Each pathway has its own multisectoral, multiregional characteristics and consequences that may be missed in more traditional modeling exercises.