Australia's main grid 50% clean for first time and supplies 30% renewable energy for a week

Source: RenewEconomy

The growth in wind, solar and battery additions to the main grid, called the National Energy Market (NEM), in eastern Australia has grown rapidly this year, particularly rooftop and large scale solar. So much so that on November 6, 2019, in one trading period, the grid had just over 50 percent of demand as renewable electricity for the first time. This was mostly solar and wind power.

Then just a few days later from November 11-17 this large NEM, ranging from Queensland to Tasmania and South Australia, produced at least 30 percent renewable energy for the entire week. This included mostly solar, wind and hydro power.

I am assuming wind and hydro supplied 30% of the demand at night as it was a windy week and hydro is big in some states. Tasmania and South Australia reach at least 30% renewables most of the time and did export to the other states during this period and on November 6.

Read More:
- Australia’s main grid reaches 50 per cent renewables for the first time. RenewEconomy, November 6, 2019.
- Renewable energy supplies more than half of Australia’s national energy market for first time. ABC News, November 8, 2019.
- Renewables supply 30% of NEM demand over an entire week for first time. Renew Economy, November 20, 2019.

UNSW student-designed solar freezer installed on a Fiji island

Source: One Step off the Grid

Engineering students from the University of New South Wales, Australia, were given a task to come up with a solution that will both empower the Fiji community and allow them to be self-sufficient. After much community consultation, they designed and installed a solar powered freezer in a remote village on Viwa Island.

“The Najia village on Viwa Island, on the outermost of the Yasawa Island group, is renowned for its fishing culture. So the students focused on creating a sustainable way for the villagers to freeze their daily catch and sell it on the mainland for more money.”

The other challenge for the students was to make sure that the project was easily maintained by the locals. Therefore the locals were trained to do the maintenance so that the freezer did not fall into disuse. Altogether the whole task was a valuable learning experience for the students and of great self-sufficient benefit to the community.

Read More:
- UNSW student-designed solar freezer installed on remote Fiji island. One Step off the Grid, November 28, 2019.
- A solar-powered freezer for today's catch: UNSW Engineering makes an impact in Fiji. UNSW Newsroom, November 27, 2019.

UK solar farm's inverter provides an overnight reactive power service

Source: NS Energy

Lightsource BP in the UK has been trialling the first night-time reactive power from a solar farm. This was achieved by using: “Specially modified electrical inverters installed at the solar facility [which] were able to transform power taken from the grid overnight – while not in use for their usual purpose of generating power from sunlight – and then feeding back optimised voltage to the grid.”

It is a way of providing a network service and in this case it is network voltage. It is also a way of adapting to a fast changing electricity network that now has a lot of solar power in the daytime. It is calculated that such an innovation will contribute to significant cost savings and additional grid capacity. Infact, Lightsource BP says reactive power could lead to £400m in customer savings by 2050.

Read more: Lightsource BP trials UK’s first night-time reactive power from a solar farm. NS Energy, November 27, 2019.

Solar energy produced “water battery” wins global award and saves 40% of university’s energy use

"Water Battery" and solar panels at the USC (USC website)

The University of the Sunshine Coast (USC), Queensland, Australia, wins an award at the 6th Global District Energy Climate Awards which was presented in Iceland in September 2019. The award was for their “water battery”, featuring 6,000+ solar panels and a thermal energy storage tank, that is cutting grid energy use at the Sunshine Coast campus by 40 percent.

The USC has a goal to become carbon neutral by 2025 and to operate sustainably. The Sunshine Coast campus uses a lot of electricity, so in order to achieve that goal they had to come up with a way to store energy without using chemical batteries which have a waste problem.

In collaboration with Veolia, the USC installed a massive rooftop solar system and built a thermal energy storage battery with a thermal chiller. When the sunshines (which is often in this location), solar energy powers the thermal chiller to cool water which is stored in a massive tank. The chilled water is used to air condition the entire campus.

Read more:
- Sunny approach to cooling campus wins global award. University of the Sunshine Coast, October 28, 2019.
- Clean Energy (How it Works): Sustainable USC, University of the Sunshine Coast.
- Sustainable USC, University of the Sunshine Coast.

A new, efficient way to capture CO₂ from the air

Diagram of the new system (MIT News)

The Massachusetts Institute of Technology (MIT) engineers have developed a new way to remove carbon dioxide (CO₂) from the air without large heat losses. The method can use any concentration of CO₂ in a stream of gas: from that of the atmosphere/air to high concentrations emitted from power plants.

The method passes gas through a stack of electrochemical plates (like a battery). The plates alternate between being charged and discharged. When air (or other gas stream) pass over the plates they are charged up and remove CO₂ from the gas stream. When the discharging cycle begins a pure stream of CO₂ is then released. Also during the discharge power is provided to drive the whole system. The cycle operates at room temperature and normal air pressure.

The air leaving the device has much less of the greenhouse gas. The resulting pure stream of CO₂ captured can be used productively to make fizzy drinks or assist with plant growth in greenhouses. Both these two industries currently use fossil fuels to make the CO₂ they need. The gas could also be compressed and injected underground for long-term disposal or, alternatively, it could be used to make fuels through a series of chemical and electrochemical processes.

Further information:
- MIT engineers develop a new way to remove carbon dioxide from the air (includes video). MIT News, October 24, 2019.
- A new paper in the journal Energy and Environmental Science by Sahag Voskian and T. Alan Hatton entitled “Faradaic electro-swing reactive adsorption for CO₂ capture.”