Where is the Best Solar?

Aaron MGDR
6 min readMar 19, 2022


It might not be a surprise to learn that solar energy capacity is not distributed evenly across the world. The top values of solar/PV power potential are found in northwest Argentina, Bolivia, northern Chile, and southern Peru, This had me pondering: Are there places being overlooked from global decarbonization perspective?

When we talk of decarbonizing the world, it is often assumed that the OECD countries should take the lead. There are good arguments for this. After all the OECD nations have the clear majority historic and current carbon emissions and are much richer. However this analysis I propose is based on two more assumptions. The first is that transitioning to renewables must require sacrifice. Yet solar is already cheaper per KWh than coal. The second is that the rates of electricity consumption will remain low in the developing world. By why would they? These nations are growing quickly, have the majority of the world’s population and access to electricity to is a key part of reducing poverty and coping with climate change itself.

Yes generally these countries are not the highest carbon emitters either per capita or in total. However, a CO2e emission is a greenhouse gas emission no matter where it originates and so if the same number of solar panels can produce more electricity then the return on decarbonization would be higher and the cost should be lower per KWh.

That’s the basis of the thesis; Go for the highest marginal wins.

Global Photovoltaic Power Potential (blue-green worst, dark red best) by the World Bank

The map above shows that only one region on earth has the highest dark-purple-red photovoltaic power potential. This Andean region touches the south of Peru, the north west of Argentina, and significant portions of Chile and Bolivia. It has solar potential of 6 KWh/KWp daily, for comparison southwest United States has 4 to 5 KWh/KWp. Most people live in places with 3–5 KWh/KWp and at the worst places such as like Northern Europe and western China get just 2 KWh/KWp.

What makes the Andes ideal for solar is that A) its high altitude results in less atmospheric dissipation of solar energy and colder temperatures mean the panels operate more efficiently, and B) The nearness to the equator mean that seasonal variation in radiance is not an issue like it is for areas further further from the equator.

A lack of seasonal variance greatly simplifies the design and planning of renewable energy grids as it removes the need to dramatically overbuild capacity, and reduces the need for long term energy storage capacity such as pumped hydro or hydrogen.

Naturally the sun still sets. For smoothing out the day / night disruption often a lithium-ion or Iron-air batteries would be the top choice however adding batteries to a grid system unfortunately means the levelized cost per watt increases. Fortunately the current energy makeup of our Andean nation offers a solution. Currently in Peru, Bolivia, and Argentina, natural gas and hydro are the two primary sources of electricity. In Chile coal and hydro are the largest sources. Although ecologically harmful in its construction, Hydro-electric has one of the lowest CO2e per KWh factors. Unfortunately climate change means that hydro-electric capacity is dwindling due to changes in precipitation, increasing the need for new production capacity. One way to solve the night problem of solar and increase utility of existing dams is use them as pumped hydro energy storage. This should help keep the LCOE down, Software modeling tools like Switch can be used to find the most cost effect route to building out clean energy.

Let’s look at how much generation these countries would need to meet there present needs keeping in mind their energy needs are growing and there is energy loss when using any storage system.
Total electricity consumption for 2019, Argentina (129 TWh), Bolivia (9 TWh), Chile (90 TWh) Peru (50 TWh). Area needed to power each country by solar (including spacing between panels).

Argentina. 0.034% of. 2,780,400 km2 or 947km2

Bolivia: 0.003% of 1,098,580 km2 or 33km2

Chile: 0.054% of 756,700 km2 or 410km2

Peru 0.013% of 1,285,220 km2 or 168km2

Even though these are small percentages of total land area they may still seem large, for comparison 2400km2 of the United States is covered in parking lots.

They all have great potential. What will be the impact of solarizing these nations? Since only Chile currently receives are large amount of its electricity from coal and has the most solar potential of all 4, placing solar in Chile will likely have the biggest impact on carbon emissions. Chile is an OECD country, and is an oil importer. Building out enough solar to electrify sectors powered by oil would make the country more resilient.

On the other hand building out solar in Bolivia would mean bringing electricity access the large part of the population that does not have it. Let us also remember that while considered better than coal natural gas effects on climate are far from neutral. Progress is being made. In 2021 an $86m 100MW solar farm, opened in Oruro, Bolivia. 70% of Its financing came from France + EU. To reach its full solar capacity investments in the coming years will need to be measured in GW to TW. and Billions to 100 Billions.

The Andes are not the only region with outstanding potential for solar electric, Namibia, South Africa, The United States, Mexico, and several middle eastern countries all stand out as well.

When I first started thinking about this I wondered if it might be that countries which use the most electricity have less solar potential while those with the most solar potential might be less developed. My thinking on this was influenced by conditions on the European continent and China, which are both significant emitters of greenhouse gasses with low solar potential. While there are big outliers, many less-developed countries — in terms of the human development index, reliability of electricity supply, and access to electricity — tend to have very high practical solar photovoltaic potential, so far untapped.

In Ethiopia just 0.005% of the country’s land area could generate sufficient power to cover existing needs, and in Mexico that figure is just 0.1%. Falling photovoltaic prices increase solar’s capacity to bring electricity to regions which have lacked it or had it unreliably.

Let us look at Namibia, a country where over half the population goes without electricity.

Namibia consumes about 1 TWh of electricity per year. Domestic sources are 347 MWH from hydro, 163 MWH from solar, 122 MWH from coal, 41 MWH from diesel and gas 7 MWH from wind. The remaining is imported from South Africa which mostly means coal.

Namibia’s average high direct solar insolation is 2200 kWh/m2/year. This is more than enough to power Namibia’s current needs, bring electricity to all its citizens, and turn the country from a net energy importer to an energy exporter.

With an abundance of electricity the country could use desalination to guarantee its citizens clean fresh water. It could produce green hydrogen for local use and export. Becoming net energy exporter would increase the stability and resilience of its economy, bolster its currency and trade balances and better prepare the country for inevitable effects of climate change. It knows it too. All of this is already part of the Namibian President’s plan for Namibia to lead southern Africa’s decarbonization.

I focused on Namibia here but with some differences similar benefits would be found by other countries that are energy importers which seek to solarize, such as small island nations.

There’s a growing movement to refer to countries who have lagged behind in terms of access to indicators of development as being not underdeveloped but as Leapfrog Nations since there is no reason they must follow the same pattern as the Western world and can instead jump to the newest tools and technology. This has already happened with mobile phones. I see no reason why it will not happen with clean energy too. A great decoupling of energy demand and carbon emission will happen.

None of this is to say that we don’t also need to decarbonize the legacy world too. In fact it is vital to, since merely keeping the currently annual levels of global CO2 emissions as they are will result to over 3 degrees warming by the end of this century, with greater and greater devastation, draught, flood, reduction of crop yields, and mass emigration, happening each year from now thru then.



co2 per watt for eu countries


[2]IEA (2020), Renewables 2020, IEA, Paris https://www.iea.org/reports/renewables-2020

current decentralized power reality — disel generators https://www.cgdev.org/blog/how-can-nigeria-cut-co2-emissions-63-build-more-power-plants