Renewable energy is necessary but insufficient

For almost everyone concerned about climate change, the nature of energy generation has been the focus of concern. Replacing carbon intense electricity generators with renewables seems simple and obvious. Today, even the most ardent supporter of sustainable living probably recognizes that the problem in achieving that isn’t just the nihilistic short-term self-interest of big oil and big coal. We just don’t know how to get there. Right now the answer isn’t more renewable energy. This is because we can't use it as is made clear by Professor Dr. Ulf Moslener of Sustainable Energy Finance at the Frankfurt School.

What actually matters is the type of energy we consume as a society. Unfortunately, there are a whole lot of constraints that inhibit both society and individuals being able to depend on renewable energy for most of their electricity needs. While a small percentage of us may choose, or need to live off the grid, this too is simply unrealistic for most of the world’s population to live sustainably. The nature of our integrated economy made up of cities, industries and transportation entirely depend on a complex system of generation, distribution and utilization. Our welfare, health and prosperity totally depend on affordable energy. It simply wouldn’t be fair to impose unaffordable increases in the cost of electricity on the less well off amongst us. While governments, business and consumers have no capacity to pay more for electricity without the loss of other important priorities.

So we have a really big problem, we need to materially reduce our carbon emissions and it has to be done cost effectively. As Bill Gates says we need an energy miracle. This problem breaks up into three simple parts. Our consumption needs to be as efficient as possible. In this area progress is being made all the time. Our electricity generation needs to be cost effective and to be available to us where and when we need it. As lots of us now understand most renewable energy today comes from solar and wind. That is because they are sources that can be generally implemented at a cost not completely outside consumer acceptance. Beyond cost, the problem with solar and wind are their volatility and intermittence. It is a big problem that wind blows and the sun shines making them intermittent. The wind and sunlight also vary in an instant making them volatile, and that happens to be a bigger problem. We need stable electricity for our appliances, hospitals and transport systems. The iceberg problem is that our distribution networks can’t cope with volatility.

“A reliable electricity system is one that maintains a balance between electricity supply and demand at all times. This balance must be sustained every second, responding to fluctuations in electricity demand throughout the day, and must be quickly restored when there is a grid disturbance” Union of Concerned Scientists Renewables and Reliability 2015

Both problems are variability, and the differences are two fold. Intermittence is more predictable and our current technology has some capacity to mitigate the variability of night and day. You may not like it but you can ramp coal and gas generation to meet our needs where the sun don’t shine. This at least means you don’t have to waste the electricity generated by day. Unfortunately, this is not true for the volatility that occurs with cloud cover and the strength of wind gusts. Our current technology is to a greater extent unable to deal with this, and as a consequence a large percentage of our wind and solar energy generated simply cannot be made available to be consumed. Grid balance cannot be maintained through balancing generation elsewhere. In theory, the addition of batteries to the network could resolve the issue. However, at this time there is little expectation that battery technology will be affordable enough to mitigate this issue for decades. Bloomberg New Energy Finance estimates that the addition of batteries would almost triple the cost of energy generated. It would however, have the advantage of then being energy we could actually use. Nonetheless, we should have reasonable assumption that battery storage will become cheaper, and that energy storage will play a role in allowing us to integrate more renewable energy to our economies.

Realistically, for a lower carbon future to be affordable, we require not just a substantial innovation in energy generation, but also in the systemic design of our electricity distribution as a whole. Without consumers being able to use affordable renewable energy we are simply shifting emissions or adding generation of marginal value.