What happens to energy security when countries actually deploy wind and solar?
Evidence from 25 empirical studies of implemented wind and solar deployment, 2015–2025.
Renewables generally improve energy security, but the gains are uneven and depend on what happens around the technology.
Wind and solar can cut exposure to imported fuels and high electricity prices, improve access to energy, and help keep power systems supplied.
But those benefits last only when grids, markets, finance, supply chains, and public institutions can support them.
Choose a part of energy security. Each section shows what changed after wind or solar was actually deployed, what helped the gain last, and what new problems sometimes appeared.
Click a section to open it
What improves
What the gain depends on
What can still go wrong
Why do the results vary?
Renewable energy can improve security, but deployment is only the starting point. Click a step to see what has to happen next.
Renewables can reduce one kind of dependence while creating another.
What helps the gains last?
The same supporting conditions appear repeatedly across the studies. Click a factor to see what it does in practice and why it matters.
What this means
Why it matters
Browse the studies
Filter the evidence, then open a study to see the chain from renewable deployment to the observed result.
Wind lowered wholesale electricity prices, but the benefit to consumers depended on how support costs and price savings were passed through.
Depends on conditions
What was deployed?
More wind generation entered the Turkish electricity market.
What changed?
Wholesale electricity prices fell, while price volatility also changed.
Why?
Cheap-to-run wind pushed more expensive generators out of the market for some hours.
What still mattered?
Retail pass-through, subsidy design, balancing, and payment for backup power.
Ayala-Chauvin et al. — Ecuador
Wind · Electricity system · Supply & reliability
The Villonaco wind farm supplied a large share of local demand, but changing output still produced periods of deficit and surplus.
Depends on conditions
What was deployed?
The 16.5 MW Villonaco wind farm was connected to the electricity system serving Loja.
What changed?
Wind met a substantial share of local electricity demand, with both shortfalls and surpluses across time.
Why?
Output varied with wind conditions rather than matching demand hour by hour.
What still mattered?
National balancing, storage, grid controls, and reliance on a single transmission connection.
Baker & Sovacool — South Africa
Wind & solar · National / industry · Supply chains & industrial capacity
South Africa added diverse, competitively priced renewable generation, while domestic manufacturing and technological control remained limited.
Mixed
What was deployed?
Wind and solar projects were procured through South Africa’s renewable-energy auction programme.
What changed?
Generation became more diverse and project prices fell, but local manufacturing stayed shallow.
Why?
Competitive bidding and lender requirements favoured established, internationally certified firms and imported technology.
What still mattered?
Foreign finance, intellectual property, warranties, specialist skills, and the durability of local jobs.
Behuria — India
Solar · National / industry · Supply chains & industrial capacity
Solar deployment grew rapidly, but India became more dependent on imported cells and modules while domestic manufacturing weakened.
Negative
What was deployed?
Solar expanded rapidly under India’s National Solar Mission.
What changed?
Imports of solar equipment rose while domestic manufacturers lost market share.
Why?
Developers had strong incentives to buy cheaper imported equipment in order to bid low prices.
What still mattered?
Industrial policy, long-term finance, R&D, and trade rules were not aligned strongly enough with deployment.
Biteniece & Dūda — Brazil and China
Wind · National / industry · Finance, ownership & supply chains
Chinese firms and finance helped Brazil expand wind capacity, while creating new dependence on foreign capital, technology, and ownership.
Mixed
What was deployed?
Wind projects in Brazil were developed with substantial participation from Chinese firms and financiers.
What changed?
Capacity and supplier diversity increased, alongside greater reliance on Chinese capital and technology.
Why?
Policy-bank finance and large state-owned firms reduced costs and made projects easier to deliver.
What still mattered?
Supplier concentration, ownership, bargaining power, and Brazil’s control over industrial development.
Cole & Banks — South Pacific
Wind & solar · Island systems · Fuel imports & reliability
Renewables reduced exposure to diesel shipments, but island-system reliability still depended on imported equipment, backup, and outside support.
Mixed
What was deployed?
Wind, solar, and related renewable programmes were introduced across South Pacific island systems.
What changed?
Diesel use and exposure to fuel-delivery disruption fell in several cases.
Why?
Local renewable generation replaced some fuel imports, while batteries and backup kept variable supply usable.
What still mattered?
Imported electronics and batteries, technicians, donor finance, diesel backup, and cyclone or marine damage.
Dean — Zanzibar
Solar · Household / community · Access, control & maintenance
Decentralised solar improved lighting and local control, but equipment failures exposed dependence on imported parts, donors, and scarce repair capacity.
Mixed
What was deployed?
Solar home systems, street lights, and small community systems were installed in Zanzibar.
What changed?
Households and communities gained more reliable lighting and some direct control over supply.
Why?
Decentralised systems could bypass weak grid service and billing arrangements.
Wind & solar · Cross-national · Technology imports
Renewable expansion increased technology imports only modestly, but trade data alone could not show how much productive capacity countries actually controlled.
Mixed
What was deployed?
Wind and solar capacity expanded across dozens of countries.
What changed?
Imports of renewable-energy equipment increased, but much less than deployment itself.
Why?
Some new demand was met through trade and some through production located inside importing countries.
What still mattered?
Trade values do not reveal ownership, domestic value added, critical inputs, or control over technology.
Fox — United Kingdom
Solar · Household · Affordability & energy vulnerability
Rooftop solar eased electricity costs and anxiety for low-income households, but benefits varied with season, daily routines, and housing arrangements.
Depends on conditions
What was deployed?
Rooftop solar was installed on low-income social housing.
What changed?
Electricity costs fell, prepaid credit lasted longer, and some households reported less anxiety.
Why?
Households used solar power directly and shifted some activities into sunny hours.
What still mattered?
Winter and evening demand, household knowledge, monitoring, grid voltage, and landlord control.
Gül et al. — Cross-country
Wind & solar · Cross-national · Energy imports
Across 47 countries, higher realised wind and solar output was associated with a modest reduction in net energy imports.
Positive
What was deployed?
Actual wind and solar generation increased across a 47-country panel.
What changed?
Countries with more renewable output tended to have slightly lower net energy imports.
Why?
Domestic renewable electricity can displace electricity or fuels that would otherwise be imported.
What still mattered?
The association was small and varied with income and infrastructure; equipment and mineral imports were outside the measure.
Joshi et al. — India
Solar · Household · Access, livelihoods & local capability
Solar study lamps reduced kerosene use and improved lighting, with local women’s assembly and repair work helping the benefits last.
Depends on conditions
What was deployed?
More than 36,700 solar study lamps were distributed in rural Rajasthan with local assembly, sales, and repair.
What changed?
Children gained better lighting and households used less kerosene; local service capacity also grew.
Why?
The lamps replaced fuel-based lighting and a nearby service network made faults easier to address.
What still mattered?
Subsidies, finance, imported components, battery and circuit failures, and programme management.
Kolb et al. — Germany
Wind & solar · Electricity system · Prices & supply
Wind and solar lowered wholesale prices and helped meet demand in tight periods, but the costs and benefits were distributed unevenly.
Mixed
What was deployed?
Observed wind and solar generation in Germany.
What changed?
Wholesale prices fell and renewable output helped cover demand when other generation was constrained.
Why?
Renewables displaced higher-cost power and supplied electricity during some tight hours.
What still mattered?
Grid upgrades, reserves, backup supply, and the way renewable-support costs were allocated.
Liebensteiner & Wrienz — Europe
Wind & solar · Cross-national · Backup investment & adequacy
More wind generation was linked to weaker investment in flexible fossil backup, raising questions about how markets pay for capacity used only occasionally.
Mixed
What was deployed?
Wind and solar generation shares rose across 14 European countries.
What changed?
Higher wind shares were associated with weaker investment in flexible gas and oil peak capacity; solar showed no clear effect at low penetration.
Why?
Renewables lowered prices and running hours for plants that provide backup, weakening their expected revenue.
What still mattered?
Storage, interconnection, demand flexibility, capacity payments, and continuing fuel-import exposure.
Liu et al. — China
Wind & solar · National · Coal imports & system integration
Wind reduced China’s exposure to imported coal, while solar initially complemented coal because manufacturing and system integration remained fossil-intensive.
Mixed
What was deployed?
Wind and solar generation expanded across China alongside continued coal use and trade.
What changed?
Wind was associated with lower coal-import exposure; solar’s early expansion did not produce the same pattern.
Why?
Wind displaced some coal generation, while solar manufacturing and integration still drew heavily on fossil energy.
Solar · Household / mini-grid · Access & fuel dependence
Rural solar systems reduced diesel deliveries and network losses, while limited capacity and replacement needs constrained the service households received.
Mixed
What was deployed?
Small household solar systems were installed in rural Cuba as an alternative to diesel-based supply.
What changed?
Diesel deliveries and network losses fell, and households gained reliable basic lighting.
Why?
Electricity was generated close to users without operating a fuel-dependent mini-grid for every service.
What still mattered?
Battery and inverter replacement, public maintenance, limited appliance use, and system capacity.
Macedo et al. — Sweden
Wind · Electricity system · Prices, trade & balancing
Wind lowered day-ahead prices in southern Sweden without uniformly increasing volatility, supported by hydropower and cross-border connections.
Mixed
What was deployed?
Wind generation increased in Sweden’s SE3 electricity zone.
What changed?
Day-ahead prices fell, while price volatility did not rise consistently.
Why?
Interconnectors and flexible hydropower absorbed surpluses and covered periods of lower wind output.
What still mattered?
Cross-border dependence, congestion, forecasting, hydro availability, and the retirement of firm generation.
Martin de Lagarde & Lantz — Germany
Wind & solar · Electricity system · Prices & investment
Wind and solar reduced wholesale prices, especially in expensive hours, while also weakening revenue for firm capacity needed during shortages.
Mixed
What was deployed?
Wind and solar generation expanded in the German electricity market.
What changed?
Wholesale prices fell, with some of the largest reductions during otherwise high-price periods.
Why?
Low running costs displaced more expensive generators and reduced scarcity rents.
What still mattered?
Backup and storage investment, demand response, network capacity, and electricity-market design.
Martinopoulos & Tsalikis — Greece
Solar · National · Fuel displacement & peak demand
Greece’s solar thermal and photovoltaic stock displaced fossil energy and grid electricity, with output aligning well with summer and daytime peaks.
Positive
What was deployed?
Solar thermal systems and photovoltaic capacity were deployed across Greece.
What changed?
Fossil-fuel use and grid electricity demand were reduced.
Why?
Domestic solar energy replaced purchased energy and produced strongly during summer and daytime demand peaks.
What still mattered?
Finance, permitting, incentives, grid and storage capacity, and stable long-term policy.
Piazza et al. — Italy
Solar · Household · Bills & price-shock resilience
Household solar reduced grid purchases and softened the effect of the 2022 energy-price and heat shocks for adopters.
Positive
What was deployed?
Rooftop solar was installed by households in and around Brescia, observed within a survey of 10,959 households.
What changed?
Solar households bought less electricity from the grid and were better buffered against price and heat shocks.
Why?
Self-consumed power replaced electricity bought at retail prices that exceeded export payments.
What still mattered?
Up-front capital, roof and tenure, tariff design, grid access, and exclusion of many renters.
Pluta & Wyrwa — Poland
Wind & solar · Electricity system · Capacity adequacy
Wind supplied a modest dependable contribution at Polish demand peaks, while solar contributed little during winter evening peaks.
Depends on conditions
What was deployed?
Hourly wind and solar generation in Poland was assessed against peak demand from 2021 to 2024.
What changed?
Wind provided some dependable capacity; solar’s contribution at critical winter evening peaks was only a few percent.
Why?
Security value depended on whether renewable output coincided with the hours when demand was highest.
What still mattered?
Storage, demand response, interconnection, backup resources, and accurate capacity-market valuation.
Quint & Dahlke — United States
Wind · Electricity market · Wholesale prices
Across nearly 79,000 hours in MISO, wind reduced real-time wholesale prices, although the marginal price effect weakened as wind penetration rose.
Positive
What was deployed?
Wind generation expanded in the Midcontinent Independent System Operator market.
What changed?
Real-time wholesale electricity prices were lower when wind output was higher.
Why?
Low-cost wind displaced more expensive generation in the market dispatch.
What still mattered?
Transmission, forecasting, flexible resources, market rules, and the investment effects of lower prices.
Riley et al. — Australia
Solar · Household · Access & affordability
Rooftop solar cut electricity spending and, during the observed period, stopped inability-to-pay disconnections.
Positive
What was deployed?
Subsidised rooftop solar on a remote First Nations public-housing household.
What changed?
Grid spending fell and observed inability-to-pay disconnections dropped to zero.
Why?
The household used more of its own electricity and earned credits for power sent back to the grid.
What still mattered?
Capital subsidy, tenancy rules, grid connection, utility cooperation, and working equipment.
Stepanov et al. — Cross-country
Wind & solar · Cross-national · Trade & material dependence
Countries with more wind and solar occupied different positions in energy and material trade, showing how deployment can relocate rather than remove external dependence.
Mixed
What was deployed?
Wind and solar capacity varied across a 64-country comparison.
What changed?
Higher deployment appeared alongside different patterns of energy, equipment, and embodied-material trade.
Why?
Building renewable systems requires traded equipment and minerals even when it reduces imported operating fuels.
What still mattered?
Concentrated mineral, panel, turbine, and battery supply chains; the cross-section does not establish causation.
Uddin et al. — Bangladesh
Solar · Household · Energy access & welfare
Off-grid solar home systems reduced kerosene use and improved lighting and household welfare across rural Bangladesh.
Positive
What was deployed?
Solar home systems were adopted across 6,712 rural household observations.
What changed?
Kerosene use fell and households gained longer, better-quality lighting and improved energy access.
Why?
Electric lighting supported study, work, communication, and access to information without routine fuel purchases.
What still mattered?
Subsidies, vendor networks, battery replacement, maintenance, affordability, and unequal adoption.
Yang & Zhan — China
Wind & solar · National / provincial · Composite energy security
Wind was associated with stronger provincial energy-security scores across China, while solar’s relationship was clearest in lower-security provinces.
Depends on conditions
What was deployed?
Wind and solar capacity expanded across 30 Chinese provinces.
What changed?
Wind correlated with higher composite energy-security scores; solar’s association was concentrated in initially weaker provinces.
Why?
Local generation can diversify supply and raise measured self-sufficiency.
What still mattered?
Grid and storage limits, intermittency, omitted supply-chain risks, and the way the composite index was constructed.
Where does the evidence come from?
This map shows the geographical coverage of the review. It does not rank countries by energy security.
Click a study location.
Cross-national studies are listed in the study browser because they do not belong to a single point on the map.
What changes when renewables are deployed?
The review suggests that renewable energy often changes where insecurity sits rather than removing it completely.
Over time
From fuel dependence to infrastructure dependence
Reliance on recurring fuel imports can fall, while dependence on grids, storage, equipment, maintenance, and manufacturing becomes more important.
Across places
Security can move between scales
A household or city can become more secure while relying more heavily on national grids, neighbouring systems, or overseas suppliers.
Across society
The gains are not shared automatically
Ownership, housing tenure, tariffs, subsidies, and market rules shape who benefits and who continues to carry costs and risks.
