After a laboratory mishap involving a consumer drone, a malfunctioning smartphone app and an impressive puff of smoke, Annebelle and Phil wake up at the controls of a two-seater quadcopter, flying over a strange land. That land is the world in 2045.
Annebelle and I are spending a few hours flying over a semi-arid area of Kenya in a two-seater quadcopter. Seeing field after field of solar panels covering many tens of hectares of land is truly impressive.
The country reached 100% renewable energy in 2031, pretty much on target – it was already at 80% a decade earlier. While most of this is geothermal, there was significant expansion of solar energy to meet the country’s burgeoning demand for electricity driven by economic development and population growth. There are now 80 million people in Kenya, up from 54 million in 2022.
Looking down, Annebelle points out a livestock farmer moving zebu cattle through a glinting field of solar panels. Thankfully, the country’s many pastoral and agropastoral households have become significantly more resilient to the warmer climate – up by about 2.5 °C since the early 1970s – and three key developments in the energy sector played a big role in this.
The first was cheap and effective off-grid energy storage. Kenya started installing sand batteries in many remote rural areas in the late 2020s. These silos contain a few hundred tonnes of low-grade sand, heated up to 500-600 °C using a solar powered heat exchanger. They enable the energy to be stored where it is generated, rather than delivered to the national grid using expensive power-line infrastructure. The energy can be stored for several months and converted to electricity as needed. By the early 2030s, sand batteries were highly cost-effective and are now widely used in Kenya’s marginal lands. This has also made locating very large solar panel arrays – like the ones twinkling below – cost effective in remote rural areas.
The second was the Kenyan government’s foresight in embracing agrivoltaics – using the same piece of land for agriculture and energy production. With appropriately designed solar panels, some raised up to 2m off the ground, the land underneath can be used for crop and livestock production. With ground or surface water in the vicinity, food and feed plants are now irrigated using electric water pumps. Until now, one problem had been that most plants don’t thrive in the shade of the solar panels.
This is where the third element comes in: the development of commercial shade-tolerant food and feed crops that can be grown in shaded conditions under the solar panels, with much reduced trade-offs in crop productivity. It took 30 years of gene editing to crack the nut of how plants regulate shade tolerance and to overcome the natural ability of many plants to actively avoid the shade. There are still some yield penalties in commercial varieties of shade-tolerant cereals and forages, but these are way more than offset by the increases in income from energy sales.
We watch as the cattle herder below pauses from time to time, letting the animals graze the shade-tolerant forage crops that share the field with the solar panels. Several of the pastoral-agropastoral farming zones in Kenya are now operating this integrated energy-agricultural system. It provides large boosts to household income from sales of crop and livestock products and energy to the national grid – plus the added advantage of reducing heat stress in both crops and livestock. This model of cross-sectoral integration could be a game changer for large parts of arid-semiarid Africa, if replicated in other countries. The environmental benefits can also be substantial, including increased water use efficiency and land productivity, and a significant contribution to renewable energy generation and reduced greenhouse gas emissions. It’s good for farmers, through increasing agricultural productivity and incomes. It has also contributed to reduced food prices in Kenya, which is good news for consumers. Although the prices producers receive for their agricultural products have also declined – albeit slightly – farmers are still well ahead because of the extra income generated from selling solar energy.
Farming both food and energy is not without its challenges, however. Shade tolerance in many plants was accomplished through gene modification. In some countries, there has been considerable social resistance to the concept of direct genetic modification, and not everyone is comfortable with the technology. The Kenyan experience highlights the need for transparency and openness in discussions with local communities. It also underscores the need for rigorous monitoring of the local impacts of implementing these production systems. Ensuring the responsible development at scale of these innovations is crucial. At the start, there were some serious challenges around accessibility and cost of seeds of the new shade-tolerant crops. These were mostly developed in the private sector and there were some serious intellectual property challenges to overcome. A few years ago, development organizations made advanced market commitments to purchase guaranteed quantities of seed at a guaranteed price. The seeds were then resold in Kenya at subsidized prices to rural farmers. This is helping stimulate the private sector to move into the African shade-tolerant seed market in a big way. It’s hoped that the intellectual property issues are ironed out soon, allowing small-scale farmers across the continent to access these varieties.
So next time you are eating ugali (maizemeal porridge) and nyama choma (grilled goat meat) in Nairobi, give a thought to how and where the maize and the goats may have come from – it might surprise you!
Now, the solar battery on this drone is telling me us we need to head back to base. So it’s over-and-out from Annebelle and from 100 m above the Kenyan rangelands in 2045.
