Basic grid-connected solar energy systems are limited in a big way. That little thing referred to as night. Jumping straight to the point, new battery storage technologies offer a good, low maintenance solution to the problem that has plagued grid-connected solar power since its mass inception over a decade ago.
It doesn’t take a rocket scientist to understand that solar power only works under certain conditions, when it’s sunny. As one of the most promising forms of renewable energy globally, solar photovoltaic cells only produce electricity when the sun shines. With battery storage, excess power produced during the day can be stored and then used it at night.
Above: The SolarWatt DC coupled solar battery integrated with an average household.
Battery storage is nothing new, however, it’s primary purpose, in this instance has changed. Combined with low maintenance lithium-ion cell technology battery storage is no longer considered solely a backup or an emergency power supply. It is an energy storage device, but for low production cost energy vs expensive grid energy.
Quite simply a remodeled version of a backup power supply. By altering the primary purpose and redesigning the product, the result is another step closer to alternative power supply dominance inspired by lower upfront costs, minimal maintenance, better performance, superior product life and greater warranties.
Lithium is where commercial viability and a reliable base material meet. There is an abundance of alternative compounds, different options and the promise of the next big thing. However, lithium is now more commercially viable than ever, combined with ultra-low maintenance properties. If manufactured and installed with integrity, lithium has proven to be a stable base material for battery storage.
Which to choose? There are plenty of new age lithium battery storage options on the market already. The features will also vary between different solar batteries and configurations. One tip, avoid unproven or unknown battery technology. It is appealing to believe the low-cost hype, but the fact is, beyond the glossy data sheet and the promise of an eternity of electricity bill freedom, severe hazards and expensive downtime exists with battery storage products manufactured on the cheap.
What to expect next?
Lithium battery storage options for solar are evolving fast. Between 2015 and 2017 the Tesla Powerwall standard battery size doubled from 6.5 kWh to 13 kWh and remained almost the same price installed within regions such as Australia. A approximate 50% reduction in the cost per kWh. Diversity in connection and retrofitting is also evolving. Previously requiring an additional battery inverter or Hybrid solar and battery inverter, certain solar battery options, such as the Tesla Powerwall 2 are shifting towards a fully integrated AC coupled solation. Meaning, the solar battery can now connect directly to electrical distribution board (switchboard) with minimal fuss or expense.
Tip: When selecting a solar battery, remember that useable kilowatt hours are the key. Needing to understand what a kilowatt hour is? Here’s the explanation on Wikipedia: https://en.wikipedia.org/wiki/Kilowatt_hour
THE BENEFITS to a good battery system are plentiful. It’s functionally eliminates the biggest downside to solar power. With a solid battery system in place, energy is produced during the day, then excess energy is stored for use at night. A battery system essentially removes the inconsistency in solar energy production. If a cloud drifts over, or alternative shading temporarily blocks your solar panels, drawing energy from the grid is avoided. There is always an element of reserve in your energy supply. Additionally, a battery system can account for the inconsistency of energy use as well as production. A household’s energy demands will vary over the course of a day. Sometimes you’ll need to turn on a few extra appliances for a while, causing your house to drain more electricity than your panels produce. If you have a battery bank, you don’t have to fear doing your washing at the same time as you cook dinner.
THE DOWNSIDE. It’s obvious but must be mentioned. If battery storage offers a solution to the greatest problem of grid-connected solar power, then why doesn’t everyone use it? The pitfall to battery storage is its current cost per kilowatt hour. Whilst the price is dropping, it remains a nice to have for many as opposed to a need to have, limiting its financial perspective. Compared to simple grid-connected solar energy, battery storage has a return on investment, in energy savings, of approximately twice that of solar panels alone based on current electricity supply charges from the grid. Aesthetic implications is a concern for some. As with most alternative energy products, it comes in the form of a large object/s which is placed on your property. If you want a battery storage solution for your home, it’s likely going to sit on a wall of the house. Of Course, most of these boxes are designed not to be aesthetically unpleasing, but they can stand out against certain architectural styles.
A reliable solar battery storage solution range between $900 – $2000 AUD per kWh, $700 – 1500 USD per kWh, or $600 – $1250 Euro per kWh installed, Starting from 6 kWh storage capacity and above. Anything less, you’re smarter than that, hence the reason you’re doing the research.
Battery storage is clearly the next step in the evolution of alternative energy supply. In theory, it completely mitigates all of the drawbacks of existing solar systems. By keeping a bit of power in reserve, when your needs exceed the capabilities of your system, you won’t start automatically drawing expensive energy from the grid.
Here’s the good news! It won’t be long before all solar energy systems come with battery storage. But for the now, battery storage is appealing to those who want to minimise their impact on the environment through eliminating grid energy draw or that can afford the upfront investment with an approximate 5-10 year return on investment plan (in energy savings).
What are your thoughts?
Are solar batteries a viable option yet? Do solar batteries meet your current expectations or is further improvement necessary? Let the world know your thoughts below.