Tesla and Solar Power in new homes

There’s lots of talk about the new Tesla Powerwall. What is it?

In most applications it’s a battery that stores the electricity generated from your solar panels in your home so you can use it when the sun’s not up.

With increasing electricity costs the push for residentially generated solar power is growing and growing in our building projects. One of the main issues with solar power for houses is that we want a lot of our power when the sun is not there; at night. Solar use in business has worked well because they need the power for the business during the day when the sun is there to generate it.

Generating electricity and storing electricity are two very different things. Many people are not aware that there is next to no storage in the electricity grid. It’s produced as we need it. When it’s hot and we all turn our air conditioners on, they have to literally load more coal into the power stations within minutes to keep up with the load requirements.

The Powerwall stores the electricity. Stored electricity can be used in a couple of ways. It can be used within your home at night (or when it’s raining), but it can also be released back into the grid on those hot days when they can’t shovel enough coal into the power stations to keep up. They pay you about 1/3 per kilowatt hour of what you pay them, but it all helps.

About 20,000 solar batteries were installed in Australia in 2017. A 3-fold increase from the year before. Who knows how many will be installed this year.

Demand is very high so prices will be high I hear you say. The good news is that part of the demand is due to significant drops in price and advances in technology. The new Powerwall 2 has twice the capacity of the original one released in 2015, but at the same price.

There are now about 20 brands of solar batteries available in Australia. Tesla is the big name but there are lots of others to choose from so the market is very competitive and prices are coming down rather than going up.

Electricity use varies greatly with different families and different efficiency of home design. But a solar system of between 3kW and 5 kW seems to be the norm, costing between $12,000 and $25,000 including batteries.

Obviously if the rest of your home is well designed from an energy efficiency perspective, the benefits and savings will be magnified.

We anticipate including solar systems in many of our building projects in Sydney this year.

Richard Hoogervorst