What is an embedded network or microgrid?

Embedded networks, also called microgrids, are privately owned and managed electricity infrastructure, usually in apartment buildings, shopping centres, airports, or multi-tenanted commercial precincts. Embedded electricity networks are grid-connected. They depend on grid power flowing through the main meter box where electricity is purchased at a bulk discount and then on-sold to tenants at reduced rates. Beyond the main gate meter, embedded networks are managed without the involvement of a traditional retailer.

Are there other benefits to embedded networks?

Yes, several!

1. Embedded networks increase electricity retailing competition and put downward pressure on energy prices.
2. By diversifying your site’s electricity mix through the addition of solar PV and solar batteries, you are future-proofing your operation, and gaining some buffer from rising electricity costs.
3. Embedded networks allow much more detailed energy management and efficiency, resulting in lower energy consumption across the board. This is not just great news in terms of showing your organisation cares about corporate responsibility and projecting an environmentally sound image into the market place, but also for Australia as a nation with the highest carbon emissions per capita in the world.
4. Billing usually happens monthly rather than quarterly, allowing consumers more control over their budgets.
5. Being able to offer stable, lower electricity prices is a great way to secure long-term tenancies for your building or precinct.

How does solar PV fit into embedded networks?

When solar PV is added to an embedded network, it will supply power at a cheaper effective rate than it can be bought from a retailer. This means the embedded network can make more revenue due to a larger markup, so it’s no surprise that facilities such as Brisbane Technology Park at Eight Mile Plains have chosen to do it. 

One of the solar rooftops that are part of the embedded network at Brisbane Technology Park

Can solar batteries be added to embedded networks?

Definitely. Adding battery storage to your solar-powered embedded network can result in even more savings by covering your site’s electricity needs at night and through the shoulder hours in the morning and evening.

The solar battery bank at Bundaberg Christian College is housed in a shipping container.

What are the key elements of embedded networks designed by GEM Energy?

1. One gateway meter that is the only point of connection to the network and therefore only one bill from the retailer for the whole site (bulk buying power provides cheaper rate).
2. Owner/tenant meters which measure the electricity consumption for each separate office or apartment.
3. Solar power system to provide energy to the embedded network even cheaper than it can be purchased.
4. Commercial scale battery such as Tesla Powerpack to maximise the self-sufficiency of the entire embedded network.

Australia’s first installed TESLA Powerpack at a school at the Cathedral College Rockhampton.

Can an embedded network with solar PV export electricity?

Yes – however, whether an export license is granted depends on local grid requirements and regulation. If export is approved, a solar-powered embedded network can generate passive income by selling unused electricity to the grid.

If export is not approved, GEM Energy can set up an embedded network with a zero-export solar system designed to cover electricity requirements on-site only. As the national electricity market and grid evolve, your request for solar electricity export might get approved in the future. In that case, we can easily upgrade your zero-export solar system to allow export.

How much will I save with a solar-powered embedded network?

This will entirely depend on the size and solar potential of your roof space, the size and energy intensity of your operation, and of course your budget.

At Brisbane Technology Park, a halving of grid power costs is expected through the addition of solar PV to the existing embedded network, plus the export of unused electricity to the main grid. The increased investment yields are sure to keep shareholders very happy. Tenants are also winning as their electricity prices will be locked in at 2017 prices for years to come.

Why do large energy users (over 100 000 kWh per year) pay less for electricity?

Big electricity users buy in bulk, so they can negotiate better rates of supply and pay lower network charges. Depending on the area electricity costs for bulk buyers may be halved. This translates into the profitability of embedded networks.

What charges make up a traditional electricity bill?

1. Raw energy costs including bulk rates negotiated with a licensed retailer – around 45%
2. Network costs – around 45%
3. Market and renewable charges including state and federal Government  levies – around 10%

Can I have an embedded network that is off-grid?

Potentially yes, however, the process is quite involved! Embedded networks or microgrids that are not grid-connected are still quite rare. Towns, suburbs, or precincts that go off-grid are commonly referred to as “microgrids in islanded mode”, as opposed to a grid-connected or hybrid microgrid that can switch between the two. There are many different microgrid examples and trials happening around the world including in rural Australia. While the technology is certainly evolving towards a decentralised electricity grid, setting up a whole town or suburban precinct as an off-grid microgrid or embedded network is a complex – and pricey – task.

For now, having the grid there as a backup is generally a good idea, but do watch this space!

Off-grid set up with solar batteries, inverters and generators