根据32年的天气数据（时间分辨率为1小时，空间分辨率为40x40 km $^2$）计算了整个美国邻近地区的风能和太阳能光伏发电数据，并假设全国各地的风能和太阳能光伏发电容量分布是基于场地适用性的随机分布。这些数据用于研究完全可再生的电力系统，主要依靠风能和太阳能光伏发电。我们发现，由于美国夏季负荷高峰，风能和太阳能光伏的季节性最佳组合约为80%的太阳能光伏份额。通过选择这种组合，长期存储需求可以减少一半以上相比，风只混合。由于太阳能光伏发电的夜间间隙，每日最佳组合约为80%的风能份额。选择这种组合而不是太阳能只能减少约50%的备用能源需求。此外，我们计算了FERC（联邦能源管理委员会）水平的LCOE（电力平准化成本）的变化，因为它们的资源质量和波动模式不同。由于地区条件的不同，LCOE的差异高达35%，LCOE的最佳组合在很大程度上取决于资源质量。基于一种新的最小成本优化方法，构建了一个FERC区域之间的传输网络增强，以传输跨FERC边界的太阳能和风能的高穿透率。
英文摘要：
Wind and solar PV generation data for the entire contiguous US are calculated, on the basis of 32 years of weather data with temporal resolution of one hour and spatial resolution of 40x40km$^2$, assuming site-suitability-based as well as stochastic wind and solar PV capacity distributions throughout the country. These data are used to investigate a fully renewable electricity system, resting primarily upon wind and solar PV power. We find that the seasonal optimal mix of wind and solar PV comes at around 80% solar PV share, owing to the US summer load peak. By picking this mix, long-term storage requirements can be more than halved compared to a wind only mix. The daily optimal mix lies at about 80% wind share due to the nightly gap in solar PV production. Picking this mix instead of solar only reduces backup energy needs by about 50%. Furthermore, we calculate shifts in FERC (Federal Energy Regulatory Commission)-level LCOE (Levelized Costs Of Electricity) for wind and solar PV due to their differing resource quality and fluctuation patterns. LCOE vary by up to 35% due to regional conditions, and LCOE-optimal mixes turn out to largely follow resource quality. A transmission network enhancement among FERC regions is constructed to transfer high penetrations of solar and wind across FERC boundaries, based on a novel least-cost optimization approach.
An autopilot for energy models -- automatic generation of renewable supply curves, hourly capacity factors and hourly synthetic electricity demand for arbitrary world regions
能源系统模型正越来越多地用于探索可变可再生能源占很大份额的情景。这需要高空间和时间分辨率的输入数据，并给建模团队带来相当大的预处理负担。在这里，我们提出了一个新的代码集与开源许可证的自动生成输入数据的大规模能源系统模型的任意区域的世界，包括国家以下地区，以及相关的通用容量扩展模型的电力系统。我们使用ECMWF ERA 5全球再分析数据以及其他公共地理空间数据集，为太阳能光伏发电、聚光太阳能发电、陆上和海上风电以及现有和未来的水电生成详细的供应曲线和小时容量系数。此外，我们使用机器学习方法来生成描述当前需求的合成小时电力需求序列，并使用区域SSP场景将其扩展到未来几年。最后，我们的代码集自动生成相邻地区之间HVDC互连的成本和损耗。我们的方法的有用性证明了几个不同的案例研究的基础上，我们的代码生成的输入数据。我们表明，尽管我们使用了全球数据集和综合需求，但我们的模型运行的未来欧洲电力系统中可再生能源的比例很高，与更详细的模型的结果一致。
Renewable energy communities (RECs) are prominent initiatives to provide end consumers an active role in the energy sector, raise awareness on the importance of renewable energy (RE) technologies and increase their share in the energy system thus reducing greenhouse gas emissions. The economic viability of RECs though, depends on multiple interdependent factors that require careful examination for each individual context. This study aims at investigating the impact of electricity tariffs, ratio of electrification of heating and transportation sectors, prices of RE technologies and storage syst…
Japan has committed to carbon neutrality by 2050. Emissions from the electricity sector amount to 42% of the total. Solar photovoltaics (PV) and wind comprise three quarters of global net capacity additions because of low and falling prices. This provides an opportunity for Japan to make large reductions in emissions while also reducing its dependence on energy imports. This study shows that Japan has 14 times more solar and offshore wind resources than needed to supply 100% renewable electricity. A 40 year hourly energy balance model is presented of Japan's electricity system using historical…
The demand for electricity and the need to replace fossil fuels by renewables have been growing steadily, and this transition will have significant implications to our world that are only beginning to be understood. Brazil is one important example of a big economy where the electricity is already supplied by renewables, such as hydro, wind and biomass-fired thermal power. In this work we investigated the electricity load curves in the last 20 years in Brazil, and four different scenarios for 2030 are proposed in order to evaluate the impact of increasing renewables in the national grid, at an …
The current governance process to plan the German energy system omits two options to substitute grid expansion: First, placing renewables closer to demand instead of where site conditions are best. Second, utilizing storage instead of additional transmission infrastructure to prevent grid congestion. In the paper, we apply a comprehensive capacity expansion model based on the AnyMOD modelling framework to compare the status quo to alternative planning approaches for a fully renewable energy system. To represent spatiality and fluctuations of renewables, the German electricity sector is modelle…
Global energy sector decarbonization efforts are contingent on technology choices for energy production and end-use in emerging markets such as India, where air conditioning is expected to be a major driver for electricity demand growth. Here, we use an integrated demand-supply framework to quantify the impacts of demand growth and temporal patterns on long-term electricity system evolution. Under projected renewables and Li-ion storage cost declines, our supply-demand modeling points to renewables contributing substantially (46-67%) to meet annual electricity demand in India by 2030. However,…
The market revenue for variable renewable electricity (VRE) assets has been under intense scrutiny during the last few years. The observation that wind and solar power depress market prices at times when they produce the most has been termed the 'cannibalization effect'. This can have a substantial impact on the revenue of these technologies, the magnitude of which has already been established within the economic literature on current and future markets. Yet, the effect is neglected in the capital budgeting literature assessing green investments in the electricity sector (e.g. including method…
Cost optimal scenarios of a future highly renewable European electricity system: Exploring the influence of weather data, cost parameters and policy constraints
As a result of the 2021 United Nations Climate Change Conference (COP26), several countries committed to phasing down coal electricity as soon as possible, deactivating hundreds of power plants in the near future. CO$_2$-free electricity can be generated in these plants by retrofitting them for iron combustion. Iron oxides produced during the process can be collected and reduced back to metallic iron using H$_2$, in a circular process where it becomes an energy carrier. Using clean energy in the recycling process enables storage and distribution of excess generated in periods of abundance. Thi…
The ambitious energy target to achieve climate-neutrality in the European Union (EU) energy system raises the feasibility question of using only renewables across all energy sectors. As one of the EU's leading industrialized countries, Germany has adopted several climate-action plans for the realistic implementation and maximum utilization of renewable energies in its energy system. The literature review shows a clear gap in comprehensive techniques describing an open modeling approach for analyzing fully renewable and sector-coupled energy systems. This paper outlines a method for analyzing t…
With growing amounts of wind and solar power in the electricity mix of many European countries, understanding and predicting variations of renewable energy generation at multiple timescales is crucial to ensure reliable electricity systems. At seasonal scale, the balance between supply and demand is mostly determined by the large-scale atmospheric circulation, which is uncertain due to climate change and natural variability. Here we employ four teleconnection indices, which represent a linkage between atmospheric conditions at widely separated regions, to describe the large-scale circulation a…
Most studies that examine CO2-neutral, or near CO2-neutral, power systems by using energy system models investigate Europe or the United States, while similar studies for other regions are rare. In this paper, we focus on the Middle East and North Africa (MENA), where weather conditions differ substantially from those in Europe. We use a green-field linear capacity expansion model with over-night investment to assess the effect on the system cost of (i) limiting/expanding the amount of land available for wind and solar farms, (ii) allowing for nuclear power and (iii) disallowing for internatio…
Solar photovoltaics which converts renewable solar energy into electricity have become prominent as a measure to decarbonize electricity generation. The operational carbon footprint of this technology is significantly lower compared to electricity generation using conventional non-renewable fuels. The operationalization of photovoltaic electricity generation however results in significant emissions which are loaded upfront into the atmosphere. An analysis of the embodied energy in Si solar panels manufacturing and installation, and associated CO2 emissions clearly show their global warming pot…
Integrating renewable energy production into the electricity grid is an important policy goal to address climate change. However, such an integration faces economic and technological challenges. As power generation by renewable sources increases, power transmission patterns over the electric grid change. Due to physical laws, these new transmission patterns lead to non-intuitive grid congestion externalities. We derive the conditions under which negative network externalities due to power trades occur. Calibration using a stylized framework and data from Europe shows that each additional unit …
