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70% efficiency is nothing to sneeze at. Stewart Island, which they envision serving with a commercial system, is powered by diesel generators with a cost of ele

70% efficiency is nothing to sneeze at. Stewart Island, which they envision serving with a commercial system, is powered by diesel generators with a cost of electricity of ~$1/kW-h. It's about 50km across the water from Bluff, where there is a surplus of energy due to a large aluminum smelter served by a dedicated hydroelectric plant. With only about 300 people, the community on Stewart Island can't justify an undersea cable. But a microwave power beaming system could be built for much less, and supply energy much cheaper (and greener) than burning diesel.

crote 6y ago
Isn't this pretty much a textbook example of hydrogen? Just ship hydrogen instead of diesel.
- filleokus 6y ago
  I wonder what the price is for the chain of Electricity -> Hydrogen by electrolysis -> Hydrogen at pressure -> Electricity by fuel cell even if the input electricity is almost free, everything hydrogen seems very expensive.
  - RobLach 6y ago
    Here you go https://www.powermag.com/how-much-will-hydrogen-based-power-cost/ https://www.powermag.com/how-much-will-hydrogen-based-power-...
    - solstice 6y ago
      Here are the relevant paragraphs: > However, a key drawback of this “power-to-gas-to-power” route, if electrolysis is used for hydrogen production, is the round-trip efficiency, which is “around 45%,” it says. The report provides an example to illustrate the cost penalty per MWh associated with the power-to-gas-to-power route: “Hydrogen generation from low-cost renewables at $25/MWh with a capacity factor of 50% yields a cost of $1.70/kg of hydrogen produced. Storing this hydrogen underground will add about another $0.30/kg, thus the hydrogen costs $2/kg. If this hydrogen is used to generate power, the resulting cost is $100 to $200/MWh. In ideal conditions (e.g. a CCGT turbine at 60% utilisation), the cost is $100/MWh, while simple-cycle turbines at 25% utilisation would deliver power at $200/MWh.” > Still, the report is optimistic. Because hydrogen production costs will drive up to 80% of total power generation costs (Figure 3), if the technical feasibility of a 100% hydrogen turbine is proven, the capital expense of hydrogen turbines could “rival that of natural gas turbines by 2030,” it says. For now, however, “companies should use hydrogen-based power for high-value flexible generation first, and two, hydrogen baseload power generation for deep decarbonisation in situations with constrained renewables potential will require strong policy support.”
Justsignedup 6y ago
would this also be the technology to use for satellite -> surface energy transfer?
- deleted 6y ago
  [deleted]
- mr_toad 6y ago
  You can’t realistically use relays in space.
- unchocked 6y ago
  Yes, it's essentially the same architecture: two large phased arrays pointing at each other. The terrestrial technology development could transfer to the space application, or vice versa.
toomuchtodo 6y ago
Island sited renewables (wind and solar) are probably a better option than high power radar through free air. Two wind turbines are enough to displace half of the diesel fired generation. Just need more turbines, solar, and some batteries. > The Provincial Growth Fund is putting $3.16 million towards building two wind turbines on Rakiura / Stewart Island > Mr Parker said building an initial two wind turbines as part of the island's power generation network was the most economic and environmentally acceptable option. > "It provides a renewable energy source. It is estimated to reduce diesel use on the island by half, which will enable the price of electricity to be stabilised." https://www.rnz.co.nz/news/political/403869/renewable-energy-government-to-give-stewart-island-3m-for-wind-turbines https://www.rnz.co.nz/news/political/403869/renewable-energy...
- Emrod 6y ago
  A number of studies have been done over the years exploring wind, solar and other alternatives. Unfortunately, they aren't perfect. non, including the two turbine solution, comes even close to providing the energy required and will still require diesel generation and LPG on the island. there is no more room for anything beyond 2 turbines on the island so it a partial solution with no scalability. Emrod can provide x5 the current energy required on the island, cheaper, replacing Diesel and LPG, future proofing supply continuity, with a far smaller environmental footprint.
  - deleted 6y ago
    [deleted]
Nition 6y ago
> where there is a surplus of energy due to a large aluminum smelter served by a dedicated hydroelectric plant. This smelter is also about to shut down in August 2021. So now there's going to be a huge surplus of electricity way down south (the smelter uses ~13% of the country's total electricity!), with the big city way up north.
- toomuchtodo 6y ago
  This is great to hear, that extra power (if the South<->North New Zealand HVDC Interconnect has the capacity [1]) will help push out New Zealand's last coal plant on the north island and possibly some of the gas generation [2]. [1] https://en.wikipedia.org/wiki/HVDC_Inter-Island https://en.wikipedia.org/wiki/HVDC_Inter-Island [2] https://www.transpower.co.nz/power-system-live-data https://www.transpower.co.nz/power-system-live-data
  - foxylad 6y ago
    We'd have to build a lot (billions) of new distribution infrastructure to get the Manapouri power to Auckland. There are a lot of ideas circulating about what to do with the Tiwai plant, including setting up a Tesla factory (it has a deep water port handy). There just happens to be a source of the purest silicon sand in the world nearby, so one intriguing option is to set up solar panel production, which given the hydro power supply would have very high sustainability credentials.
    - toomuchtodo 6y ago
      Really like the solar idea, with Australia a short jaunt away by sea and them having an enormous solar potential.
tus88 6y ago
Sounds like you just blew all the arguments for solar/wind energy out of the water.

crote 6y ago

Isn't this pretty much a textbook example of hydrogen? Just ship hydrogen instead of diesel.

filleokus 6y ago
I wonder what the price is for the chain of Electricity -> Hydrogen by electrolysis -> Hydrogen at pressure -> Electricity by fuel cell even if the input electricity is almost free, everything hydrogen seems very expensive.
- RobLach 6y ago
  Here you go https://www.powermag.com/how-much-will-hydrogen-based-power-cost/ https://www.powermag.com/how-much-will-hydrogen-based-power-...
  - solstice 6y ago
    Here are the relevant paragraphs: > However, a key drawback of this “power-to-gas-to-power” route, if electrolysis is used for hydrogen production, is the round-trip efficiency, which is “around 45%,” it says. The report provides an example to illustrate the cost penalty per MWh associated with the power-to-gas-to-power route: “Hydrogen generation from low-cost renewables at $25/MWh with a capacity factor of 50% yields a cost of $1.70/kg of hydrogen produced. Storing this hydrogen underground will add about another $0.30/kg, thus the hydrogen costs $2/kg. If this hydrogen is used to generate power, the resulting cost is $100 to $200/MWh. In ideal conditions (e.g. a CCGT turbine at 60% utilisation), the cost is $100/MWh, while simple-cycle turbines at 25% utilisation would deliver power at $200/MWh.” > Still, the report is optimistic. Because hydrogen production costs will drive up to 80% of total power generation costs (Figure 3), if the technical feasibility of a 100% hydrogen turbine is proven, the capital expense of hydrogen turbines could “rival that of natural gas turbines by 2030,” it says. For now, however, “companies should use hydrogen-based power for high-value flexible generation first, and two, hydrogen baseload power generation for deep decarbonisation in situations with constrained renewables potential will require strong policy support.”

Justsignedup 6y ago

would this also be the technology to use for satellite -> surface energy transfer?

deleted 6y ago
[deleted]
mr_toad 6y ago
You can’t realistically use relays in space.
unchocked 6y ago
Yes, it's essentially the same architecture: two large phased arrays pointing at each other. The terrestrial technology development could transfer to the space application, or vice versa.

toomuchtodo 6y ago

Island sited renewables (wind and solar) are probably a better option than high power radar through free air. Two wind turbines are enough to displace half of the diesel fired generation. Just need more turbines, solar, and some batteries. > The Provincial Growth Fund is putting $3.16 million towards building two wind turbines on Rakiura / Stewart Island > Mr Parker said building an initial two wind turbines as part of the island's power generation network was the most economic and environmentally acceptable option. > "It provides a renewable energy source. It is estimated to reduce diesel use on the island by half, which will enable the price of electricity to be stabilised." https://www.rnz.co.nz/news/political/403869/renewable-energy-government-to-give-stewart-island-3m-for-wind-turbines https://www.rnz.co.nz/news/political/403869/renewable-energy...

Emrod 6y ago
A number of studies have been done over the years exploring wind, solar and other alternatives. Unfortunately, they aren't perfect. non, including the two turbine solution, comes even close to providing the energy required and will still require diesel generation and LPG on the island. there is no more room for anything beyond 2 turbines on the island so it a partial solution with no scalability. Emrod can provide x5 the current energy required on the island, cheaper, replacing Diesel and LPG, future proofing supply continuity, with a far smaller environmental footprint.
- deleted 6y ago
  [deleted]

Nition 6y ago

> where there is a surplus of energy due to a large aluminum smelter served by a dedicated hydroelectric plant. This smelter is also about to shut down in August 2021. So now there's going to be a huge surplus of electricity way down south (the smelter uses ~13% of the country's total electricity!), with the big city way up north.

toomuchtodo 6y ago
This is great to hear, that extra power (if the South<->North New Zealand HVDC Interconnect has the capacity [1]) will help push out New Zealand's last coal plant on the north island and possibly some of the gas generation [2]. [1] https://en.wikipedia.org/wiki/HVDC_Inter-Island https://en.wikipedia.org/wiki/HVDC_Inter-Island [2] https://www.transpower.co.nz/power-system-live-data https://www.transpower.co.nz/power-system-live-data
- foxylad 6y ago
  We'd have to build a lot (billions) of new distribution infrastructure to get the Manapouri power to Auckland. There are a lot of ideas circulating about what to do with the Tiwai plant, including setting up a Tesla factory (it has a deep water port handy). There just happens to be a source of the purest silicon sand in the world nearby, so one intriguing option is to set up solar panel production, which given the hydro power supply would have very high sustainability credentials.
  - toomuchtodo 6y ago
    Really like the solar idea, with Australia a short jaunt away by sea and them having an enormous solar potential.

tus88 6y ago

Sounds like you just blew all the arguments for solar/wind energy out of the water.