CLEAN ENERGY

Just 10% of global energy production is from renewable technology. These technologies are not entirely ‘clean’. Manufacturing wind turbines and solar panels does come with a carbon cost and they have great limitations. The sun doesn't always shine, and the wind doesn't always blow.

You could ask why not just put millions of solar cells in the sunniest parts of the world?

The problem is this is not where the power is needed and most electrical grids operate relatively independently. In the US for example there is no single grid given the vastness of the country, rather it is served by localized grids. This is the case even in many countries much smaller than the US.

So, putting hundreds of square miles of solar panels in Arizona isn't going to be able to power the entire US unless the cost of electricity transmission dropped twentyfold. The same is the case for wind and wave, many countries are landlocked with no access to wave power, while central continental countries have far less wind than countries with big coastlines. On top of location and power transmission the other problem with renewables is cost. Burning fossil fuels is extremely cheap per kilowatt produced.

Even if a country could produce the majority of its energy from wind or solar it cannot be used all at once and the sun doesn't shine at night, so storage is the answer. But today, storage per kilowatt is still far too expensive to make it a viable option on a scale basis.

This does not mean solar and wind, or geothermal and hydro are never going to get there, there are massive advancements taking place, but they cannot be treated as the solution in isolation.

SOLAR

Almost all life on earth is powered by the sun. Solar cell technology has been around for over 50 years, but it is only in the last 10 years that photovoltaic cells have advanced in capacity and cost to make them a really viable energy production solution.

The amount of energy the sun sends us in an hour is enough to power the world for over a year. Solar could power the entire Earth, but right now it is not economical enough and storage not cheap enough to make it viable. Also in densely populated small countries, like the Netherlands for example, the amount of land area required to create enough energy for the population simply wouldn't be enough.

Advancements in see-through transparent solar cells have taken place, which could ultimately lead to large buildings having electricity generating glass for windows. There is no shortage of ideas for integrating solar, such as solar roads where solar panels are built along the medians, even floating solar cells in lakes, for cooling. These technologies are known as building integrated photovoltaics (BIPV). These new inventions and concepts are likely to significantly increase the percentage of solar energy over the next decade.

Solar panels that follow the sun can also help maximize efficiency; many solar farms tilt and pivot towards the sun's rays, known as photovoltaic trackers.

Instead of rather ugly solar panels on rooftops, Tesla and others have developed roof tile style integrated cells to camouflage the panel into the roof.

Once again cost is the issue, as these technologies are relatively new and still at a very high price point per kilowatt of electricity compared to fossil fuel.

Producing solar panels on a massive scale is another challenge. Over half of the world’s supply of polysilicon comes from just one region in China.

WIND

Like solar, wind power is getting cheaper. In the year 2000, 17,000 megawatts of global wind power were produced, while in 2020 this was 600,000 megawatts, avoiding over one billion tons of CO2 globally. Advancements in the composites used to build giant wind turbines has accelerated in recent years and the use of offshore wind farms to maximize exposure to more consistent wind has increased, with several massive projects both in Europe and the US.

In the UK the increasing use of wind energy has reached record levels. Wind produced energy is growing at a faster rate than solar, but the capital-intensive nature and high maintenance of wind turbines is a negative.

New technologies known as solid state wind energy have been developed where no blades or rotation is used. These technologies offer an alternative for harnessing wind power and work on the principle of converting electrostatic wind energy to electricity. The technology creates a flow of charged particles from the movement of the air by spraying fine positively charged water droplets into the air flow, creating particle movement and electricity. Prototypes of this technology have already been established in the Netherlands.

Other technology concepts like solid state wind energy transformer works off the same principle but without water. Other concepts using wind to create vibration energy are also in development.

While large wind turbines can't be installed in cities, rooftop solutions, such as the bladeless power pod from Utah based startup Halcium, offers the possibility of portable wind energy where all moving parts are contained within a pod like cylinder. These designs dispense with the need for heavy mechanical parts and rotor blades and if successful will be game changing microgrid options in cities.

WE NEED TO WEAN OURSELVES OFF FOSSIL FUELS

During Easter 2021, due to a combination of sunny and windy weather, 80% of the UK's power came from renewables, 39% wind 41% solar.

But renewable energy is not all about the sun and wind. In the US it is estimated that coastal wave energy could power almost 70% of the country. Wave and tidal power are more consistent and predictable than the sun or wind and has the potential to be even cheaper per kWh than wind or solar.

Renewable energy is mostly accelerating in developed countries. As developing nations race to achieve the living standards of the west, new fossil fuel fired electricity stations are still being built today. This is purely a cost issue, as renewables just can't compete due to intermittency and storage cost. Germany brought its last new coal power plant online as late as 2020, even though Germany

plans to close all its 84 coal fired power stations by 2038. In China although president Xi Jinping pledged to make the country carbon neutral by 2060, the country still added almost 40 gigawatts of new coal fired power capacity in 2020. Our fossil fuel addiction is hard to kick.

Scientists estimate we're going to run out of oil and gas before the end of the century. With increasing fossil fuel costs, bringing the cost of renewables down is vital to meet the Paris Agreement targets in any meaningful way. So, just how close are we to renewables beating the cost of fossil fuel electricity? The cost of solar and wind has reached the point where it is cheaper than coal power in many cases according to the International Renewable Energy Agency (IRENA). Solar and wind is also more efficient as fossil fuel generation has reached peak efficiency.

But the cost of making electricity is only part of the problem, because a coal, gas or oil plant can be effectively switched on and off on demand when needed, unlike renewables. Renewables that are cheap and accessible to many is just half the problem; cheap storage is the other half and I’ll be covering that in a future blog.