Innovation in renewables: Energy storage


The biggest issue with Solar and Wind power is that they aren’t 100% reliable. Solar obviously only works during the day, which depending on latitude and the time of year means panels can produce little or no electricity for extended periods of time, while wind turbines also become less effective when there is little or no wind to push their blades. To solve this problem, many companies and research institutions are working on improving energy storage technology so these gaps in production can be bridged better without having to resort to traditional energy sources such as fossil fuels.

Using batteries to achieve this isn’t innovative, what is new is the focus on distributing the solution directly to people’s homes so that each household can have its own energy storage system that allows it to function with Renewable Energy when the two main sources, solar and wind, aren’t supplying the grid with enough power. The most famous example is Tesla’s Powerwall, presented the famed Elon Musk just a few months ago.

Renewable energy storage

How will these batteries work?

The Powerwall is a lithium ion home battery system that when installed will be able to store and replace grid electricity when there is no renewable energy supply. Lithium batteries are very common, they power most of our electronic devices such as phones and laptops, but what Tesla wants to do is create a giant version that can store enough energy to power an entire house for hours at a time. The Californian company began taking pre-orders for the device right after it was announced in May of this year, and according to many accounts these filled up very quickly. To make all these batteries Tesla is building a massive manufacturing plant which has been named Gigafactory. Scheduled to be completed in 2016, the plant will supposedly measure a gargantuan 10 million square feet.

But Tesla isn’t the only company working on high tech batteries, nor is Lithium Ion the only technology that is being developed. Another company working on the technology is Imergy Power Systems, which is pioneering a different battery technology: Vanadium.

Vanadium batteries are more stable than Lithium Ion, and unlike the latter, their lifespan can extend for multiple decades. Anyone that has used a device with a Li-ion battery extensively knows that over time the battery’s efficiency and performance begin to drop. Depending on the characteristics of the device itself, this can render it unusable after a few years unless a replacement is purchased. This experience is all too common with phones and laptop computers, which after a few years of intense usage can see their battery performance diminished to just a fraction of its original duration.

Vanadium’s unique chemical properties offer a solution to the issue of battery degradation, very important for the types of systems Imergy and Tesla are developing whose goal is to provide a long-term, reliable energy supply to our homes so these can be more sustainable.

What impact will these systems have on how we use energy?

The biggest advantage of having reliable electricity storage in our homes is that it would allow us to choose what kind of electricity we want to consume. All the electricity that flows through the grid is the same stuff, but it isn’t all produced in the same way. In most western countries there is a variable mix of electricity produced by burning natural gas, coal, or petroleum derived fuels at thermal plants, nuclear, hydro turbines, solar, wind, and a few others that are specific to certain regions’ unique characteristics. Some of these sources are environmentally friendly, such as solar and wind, while others are not. Depending on where you live the amount of energy that can be produced by renewable sources can vary quite a bit because on how many hours of daylight you have. Solar panels only work during the daytime, so if you can’t somehow store that energy at night you’ll by default be consuming electricity from other sources.

With energy storage systems a connected home could be energy-independent during times when the renewable electricity feed into the grid is low or non-existent. Furthermore, it will also enable homes with their own renewable generation systems, such as rooftop solar panels, to create and store their own electricity so as to be much more self-sufficient.

The other effect these systems will have on our energy ecosystem is decentralization. With the number of homes with renewable energy systems constantly growing, equipping them with energy storage capabilities will allow them to go off grid for longer periods of time. This will reduce the total volume of electricity that is consumed (and therefore generated) through traditional means, while also putting pressure on large utility companies to adopt better practices or risk losing consumers.

In locations where successful community energy projects have been set up, consumers will be able to choose when to charge their home battery systems so as to maximize their renewable energy potential. If a local solar farm is at it’s most productive from 10 in the morning to 5 in the afternoon, home battery users will be able to charge their system during those hours, saving electricity while the quota supplied to the local grid from renewable sources is at its highest, and then switching to battery use in the evening and at night when gas-powered thermal plants are revving up.