There are several key economic barriers that currently hinder the wider adoption of renewable energy technologies on a global scale:

Higher Upfront Investment Costs: Renewable energy sources like solar, wind, hydro and geothermal generally have higher upfront capital costs for initial investment compared to fossil fuel options. This is because building renewable energy infrastructure requires expensive equipment and specialized components. The higher costs pose challenges for widespread consumer adoption as well as investment by utilities and energy providers.

Lack of Grid Parity: Most renewable energy technologies have still not reached grid parity with conventional fossil fuel sources on an unsubsidized basis. This means that in many locations and market conditions, electricity from renewable sources is still more expensive to produce than electricity from coal, natural gas or oil-fired power plants. Achieving lower generation costs through economies of scale, technology improvements and elimination of subsidies for fossil fuels is necessary for grid parity to be reached globally.

Intermittency Issues: The intermittent and fluctuating nature of many renewable energy sources like solar and wind presents economic challenges related to energy storage, grid balancing and backup generation needs. The costs of developing large-scale storage solutions and updating transmission infrastructure to accommodate more renewable integration have slowed more ambitious renewable energy commitments in some jurisdictions. It also reduces the economic value proposition for renewables compared to “always on” fossil fuel generation.

Higher Financing Costs: Due to technology risk perceptions, complex project structures and long payback periods, renewable energy projects generally face higher costs of debt and equity financing compared to conventional generation. Lenders view renewable projects as riskier investments given technology uncertainties and lack of operating track records for some technologies. Higher borrowing costs compound the upfront capital expenditure challenges.

Land Use Constraints: Deployment of renewable energy infrastructure requires significant amounts of land area, which drives up costs. For example, solar and wind projects need large footprints for panels/turbines as well as spacing between installations. Competing land demands for agriculture, urbanization and conservation add scarcity value and make acquiring suitable parcels of land more costly. This “land use” economic barrier is especially pronounced for small urban/residential deployments.

Limited Revenue Streams: Unlike fossil fuel plants that generate revenues through steady baseload power sales, the intermittent nature of most renewable sources means projects have less predictable cash flows over time from energy/capacity revenue alone. This complicates long-term revenue and financing projections, as does lack of firm contracts for offtake at suitable prices. Policy support mechanisms have helped address this but come with administrative burdens and costs.

Supply Chain Bottlenecks: Renewable deployment at massive global scales envisioned will require scaling up specialized manufacturing and assembly operations for components like solar panels, wind turbines, geothermal heat exchangers as well as critical minerals processing. Increasing production rapidly while maintaining quality control and minimizing waste is challenging and costly. Supply chain gaps create short-term price inflation as demand outstrips manufacturing scale-up.

Market Distortions from Fossil Fuel Subsidies: Government subsidies provided globally to the oil, gas and coal industries around $5.9 trillion USD annually according to the IMF distort energy markets in favor of fossil fuels. These incentivize continued coal/gas power plant construction and undermine the ability of renewables to compete fairly without policy support measures of their own. As long as such fossil fuel subsidies persist, they act as an economic barrier against a renewable transition.

While renewable energy costs have declined significantly in recent years, overcoming substantial structural economic barriers like high upfront capital requirements, financing challenges, land constraints and market distortions from remaining fossil fuel subsidies will be crucial to accelerate the global energy transition at the scale and pace needed according to climate change mitigation scenarios. Considerable policy, regulatory, industrial and technological advancements are still needed to make renewables more economically competitive globally on an unsubsidized basis.