Nrel Efficiency ChartEdit

The NREL Efficiency Chart, often called the Best Research-Cell Efficiency Chart, is a visualization produced by the National Renewable Energy Laboratory that tracks the best laboratory efficiencies reported for solar photovoltaic devices under standardized testing. Updated as new records are verified, the chart provides a historical snapshot of how far solar science has advanced and what technologies are pushing the frontier. It serves as a reference point for researchers, policymakers, manufacturers, and investors who care about the long-run cost and reliability of solar power.

The chart makes clear that progress in solar technology is not a single story but a family of stories across different materials and device architectures. It covers a spectrum of technologies—from crystalline silicon to cadmium telluride, copper indium gallium selenide (CIGS), and the more exotic families of III-V multijunction cells, as well as the rapidly evolving perovskite devices and tandem configurations. Because the chart focuses on lab-record efficiencies under standardized conditions, it highlights what is technically possible, even as market realities—costs, durability, supply chains, and manufacturing scale—play out differently in the real world. The numbers reported are typically under 1-sun illumination and the AM1.5 spectrum, with tests conducted at or near 25 C; the chart also distinguishes single-junction and multi-junction performance, and it is regularly updated as new records are confirmed. National Renewable Energy Laboratory Best Research-Cell Efficiency Chart

Technologies represented - Crystalline silicon (c-Si) remains the backbone of commercial solar, and the chart shows that lab records for silicon-based cells have hovered in the mid-to-high 20s percent, with ongoing improvements in passivation, optical design, and manufacturing. This family of cells dominates the market, and its progress has a direct bearing on the cost-per-watt of installed solar systems. See also Crystalline silicon solar cell. - CdTe (cadmium telluride) cells are another established non-silicon technology. Lab records for CdTe sit in the low 20s percent, with advantages in certain thin-film manufacturing contexts. See also Cadmium telluride solar cell. - CIGS (copper indium gallium selenide) is a flexible thin-film approach that records in the low-to-mid 20s percent range in the lab, with potential for lightweight and curved applications. See also Copper indium gallium selenide solar cell. - III-V multijunction cells (for example, GaInP/GaAs/Ge stacks) are among the highest-efficiency devices demonstrated in labs, frequently pushing toward the 30s percent range under specialized conditions; such devices are central to high-performance applications, including space and concentrated photovoltaics. See also III-V solar cell. - Perovskite solar cells have emerged as one of the fastest-moving segments in solar research, with rapid gains in efficiency in the lab and strong momentum for tandem configurations with silicon. See also Perovskite solar cell. - Tandems and multi-junction stacks (for example, silicon/perovskite tandems or other combinations) target efficiencies well into the 30s percent in research settings, by stacking materials with complementary absorption. See also Tandem solar cell. - Organic photovoltaic (OPV) devices and other emerging thin-film concepts appear in the chart as exploratory technologies, signaling long-run potential even if commercialization remains limited. See also Organic solar cell. - The chart also sometimes highlights the gap between laboratory efficiency and module efficiency, reminding readers that real-world performance depends on durability, temperature behavior, and packaging. See also Module efficiency.

Trends and interpretation - The chart demonstrates sustained progress across multiple material families, but the rate of progress varies by technology. Silicon remains dominant in the market, while tandem and perovskite research show the strongest potential for significant gains in a cost-competitive era. See also Levelized cost of energy. - A key implication of the chart is that scientific breakthroughs do not automatically translate into cheaper electricity. Real-world factors—manufacturing scale, supply chains, degradation, and system design—shape the ultimate economics of solar. See also Economies of scale. - The chart serves as a barometer for public and private research investment. Stable, predictable funding coupled with a clear regulatory horizon tends to attract private capital and accelerate development, while policy uncertainty can slow progress or misallocate resources. See also Industrial policy.

Controversies and debates - Lab progress versus market viability: Critics note that a rising efficiency curve in the lab does not guarantee rapid declines in installed system costs. The path from lab-record cells to durable, low-cost modules involves manufacturing breakthroughs, yield improvements, and long-term reliability tests. Proponents argue that high-efficiency research creates downward pressure on all downstream costs and expands the feasible design space for future markets. See also Cost of solar power. - Substitutability of policy tools: Proponents of a market-driven approach argue that stable funding for basic and applied research, plus predictable tax and trade policies, is more effective than ad hoc subsidies aimed at specific technologies. Opponents of market-only strategies claim certain early-stage investments are necessary to overcome natural monopolies in supply chains and to reduce risk for private capital. See also Energy policy. - Resource and supply-chain concerns: Some critiques emphasize potential bottlenecks in critical materials (for example, indium, gallium, tellurium, and selenium) that could affect large-scale deployment of high-efficiency devices. Supporters respond that ongoing materials research and diversification of supply chains mitigate these risks, and that policy can encourage domestic processing and recycling. See also Critical materials. - Domestic manufacturing versus global competition: The chart reflects U.S. and global research leadership, but debates continue about where manufacturing should be located and how to safeguard domestic jobs without hampering competitiveness. Supporters argue for a balanced industrial policy that rewards private investment and U.S. supply chains; Critics worry about distortions and prefer minimal government intervention. See also Industrial policy. - Woke criticisms and energy strategy debates: Some commentators argue that energy policy should foreground social equity and environmental justice, potentially at the expense of aggressive efficiency gains or rapid deployment. From a pragmatic vantage, supporters contend that steady, market-friendly innovation—backed by transparent cost-benefit analysis—delivers long-run improvements in affordability and reliability, and that focusing narrowly on equity goals can slow progress and raise costs for consumers. See also Energy justice.

See also - Best Research-Cell Efficiency Chart - National Renewable Energy Laboratory - Solar cell - Crystalline silicon solar cell - Perovskite solar cell - Copper indium gallium selenide solar cell - Cadmium telluride solar cell - III-V solar cell - Levelized cost of energy - Energy policy - Industry policy