Renewable Energy - Megathread

I believe we already have solar-powered carbon capture & sequestration technology. Vegetation. I’d like to see any artificial technology that can compete on grounds of cost and effectiveness.

One I particularly like is algae from sewage. The algae can be harvested for biofuel. In the process, they draw carbon dioxide from the atmosphere and consume nutrients from the sewage.

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One of the videos I watched on the Carbon Engineering topic had a guy holding a jar with a clear liquid saying it was a simple process and cost effective to create it - the same fuel that drives your car or truck or tractor, petrol (gas) or diesel … it was at that point I felt a little too much was being ‘simplified’ as I’m usually fairly careful to ensure I get the right pump at the servo for the vehicle I’m filling … In another video they make some fluffy statements including that heavy vehicles can’t run on battery power, which set a distant but easily recognised bell ringing for me and I scoured the horizon for ‘el toro’. Maybe battery power isn’t practical in a heavy vehicle sense today, but that was a big and final sounding generalisation especially given that Tesla (hybrid) and others are playing with ideas in this area. Of course videos are often far more marketing than any real ‘evidence’ …

This is not an area of expertise for me, except to say I enjoy using fuel in various vehicles :slight_smile:

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Tesla certainly already have a battery powered truck, as do a number of other manufacturers who either have one or have a prototype, including at least Volvo and Ford/DHL from memory, and perhaps others are working on it too now.

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Indeed - and the other thing in the back of my mind was how appropriate electric motors are to high torque requirements as with heavy vehicles, something about generating max torque near stall/etc? from memory - and how they can be deployed at the wheels - like with the huge mining trucks - used for dynamic braking, which I imagine might simplify drive train mechanics and give options for power recovery. Locomotives also use electric drive … so I think I heard the right bell going off :slight_smile: even if my engineering is vague at best …

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Lets not forget my tractor in all of this. Instead of 600kg of water ballast in the rear wheels there could be a 600kg battery. Perhaps for a 16 hour ploughing session it might not last, but for the hour or two at a time many of us need it would be a good way to repurpose older machinery with diesel power.

No need even for a more expensive high energy density battery to store that renewable goodness, as weight is not a problem. It’s lack of weight that is usually a problem. Accepting this is more a suggestion about how we can leverage off renewables it may also be one more opportunity that the Govt and Elec retailers can’t touch.

Drifting back towards renewables more directly:

  1. What is the scope or definition of renewables for energy?
  2. What is the scope of the secondary sources of energy that are enabled by or created using renewables. EG battery storage, or syngas?
  3. For each renewable energy there are options that are in use, others that are emerging (proven, costed early adoption), and some that are not here yet as the are either technically not ready or are too high cost?
  4. For each renewable which need or needs does it best meet?

Wiki to the rescue:

The original proposition of this topic appears to be simply about the potential for the cost of electricity to be driven down by the uptake of renewables in that sector. There was an alternate proposition perhaps doubting how this might manifest itself in reality given the influence of Government and interests or effects of Energy Retail/Distribution on final consumer pricing.

How can we continue to add for other consumers further value to this topic?

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So is BIO-Methane a truely renewable energy source or is it an alternate fuel source?

It only exists for as long as we produce waste that can be turned into Bio-Methane. It arguably captures and converts methane which would otherwise have been lost to the environment as a very bad greenhouse gas, which is good. Typically sources usually also produce some CO2. When it is burnt it is still a hydro carbon which adds more (about half that of other liquid or solid fuels) CO2 to the environment.

There are already numerous small scale plants around Australia producing power from bio mass. Per those in the following with landfill as the energy source.

And surprisingly a large number on natural gas, all of which are much lower emitters of green house gas than coal or liquid hydrocarbon fuels.

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It’s created (not extracted), then consumed, so why not?

Are they?
https://gisera.csiro.au/factsheet/fugitive-methane-emissions-factsheet/

Or a slew of other types of storage:

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It’s created (not extracted), then consumed, so why not?

Are they?
https://gisera.csiro.au/factsheet/fugitive-methane-emissions-factsheet/

Or a slew of other types of storage:

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Also if the bio-methane is not captured in many situations it will be released to the air, the garbage, manure or whatever will ferment anyway. Methane has a much more effect on climate change than CO2.

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Only if the calculation is limited to comparing the emissions from burning. If you include fugitive emissions of methane during extraction and transport the story changes dramatically. The CSG industry tries to pretend the fugitive emissions are negligible or at least unquantified. The lack of comprehensive data at gas fields is because the industry doesn’t want the data available and State governments don’t insist.

A perverse outcome of the CSG export boom is that gas has become so expensive that less is now burned for power than if export didn’t occur.

The idea of methane as a transition fuel is somewhere between unproven and a total furphy.

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yep, just now. Sorry, it was me …

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Hope a single response will suffice.

Wikipedia has a slightly different take on the definition:
Renewable energy is energy that is collected from renewable resources, which are naturally replenished on a human timescale, such as sunlight, wind, rain, tides, waves, and geothermal heat.

It seems to ignore or sidestep energy derived directly from biological material:
I have tried to reduce this to a simple set of Yes/No propositions. There is no need to answer them. It’s more a challenge to ask how good bio-fuels may or may not be as a long term solution compared to other options. Given we have way too much carbon dioxide and methane in the environment already.

  1. Is it this way because there is an element of consumption or removal from the system?
  2. Is a key need with biomass derived energy ensuring there is a balance between carbon emissions and recovery?
  3. Is it relevant to ensure any process does not add carbon to the environment faster than the original source can take it back?
  4. Should we avoid using Biomass if it increases carbon in the atmosphere?

I recollect the comparison was specifically comparing emissions from natural gas with coal and liquid hydrocarbon fuels (EG oil. diesel etc).

Noted the link provided a useful reference on the nature of Fugitive Emissions from Coal Seam Gas extraction CSG.

The Australian Dept of Environment, Annual Reports and Quarterly Assessments and Forecasts are a more complete point of reference for the relative levels of emissions for each energy source and national statistics. It includes fugitive emissions in it’s overall assessments. Energy derived from gas has significantly lower emissions, typically half that of coal when used for electricity generation per the reports.

Storage systems for energy to complement renewable energy sources or support lower greenhouse gas emission strategies looks like it could be a topic on its own.

Think it through. From where does the material that comprises the biofuel come? To where does that material go when the fuel is used?

You seem to be over-thinking. Natural systems are balanced. Humanity has upset the balance(s).

I have.

When we create and use biomass we are intervening in a natural system. It may help all of us to do so, but the balance is not as it once was. And perhaps wisely we should also be mindful of that when we do.

There are numerous projects that currently leverage off biomass. Most are making better use of waste than letting it add methane to the environment. I hope they continue as they also provide a better source of gas for power generation than new extraction and have a net positive outcome compared with doing nothing.

As emissions from landfill are included in the national greenhouse gas accounting it is also a measurable resource.

For all those who did not watch ABC Landline last Sunday, it would be well worth your while to watch it on ABC iView or on the ABC website, especially the segment on growing blue agave plants in FNQ.

As well as providing biomass to run the mill and export base load electricity all year round to power 28.000 homes, and to produce high value wax products for the cosmetics industry, the mill will also produce some 55 million litres of ethanol per annum.

That is enough to provide the ethanol component in 550 million litres of E10, so for those motorists who use 50 litres a week, that is enough to power over 210,000 vehicles annually.

The other segments featuring shooting on a WA cattle station and the history of the Australian Cattle Dog and the Kelpie were also very interesting.

It’s an interesting observation. Is the use of biomass for vehicle fuel the best resource use? Or also to reduce greenhouse emissions in the transport industry?

The alternative might be to use the ethanol as fuel for combined cycle electric power generation at between 55% and 60% efficiency, rather than burn it in a motor vehicle at 25% efficiency. It produces a greater carbon reduction as an offset against coal as a fuel than as a replacement for petrol or LPG etc. The other option is the use as a renewable fuel for aviation which remains hydrocarbon dependent.

Does this mean cheaper electricity or air travel? Probably not as the natural gas now in use is a cheaper fuel for electric power generation, and aviation fuel might require an upgrade of the ethanol production to a more energy dense fuel to achieve the same overall performance and range as modern Jet-A.

What ever the direction with a five year lead time to maturity of the crop, it would need to scale up rapidly to be a significant energy source. Per the ABS 9309.0 in Jan 2018 there were 19.2M registered vehicles on the roads with 75% petrol powered (approx 14.2M).

The scale of what is needed whether the ethanol went to blended E10 or elsewhere is dramatic. It would take a total of 68 similar projects to power the whole of the Aussie petrol fleet with local E10. Take it further to an e85 blend which can have a higher octane RON 107. That’s 740 similar sized projects or more if you discount ethanol is approx 26% of the energy content compared to petrol. Interesting car options too as it works in a V8 Bathurst car?

https://www.unitedpetroleum.com.au/fuel/e85/
https://www.racq.com.au/cars-and-driving/cars/owning-and-maintaining-a-car/facts-about-fuels/e85-fuel

Not sure if the larger tank size needed will catch on for 2 wheeled enthusiasts?

Is that what’s proposed? The term biomass generally refers to fibre. Usually lignocellulose.

The project in question involves using all parts of the agave, but burning the fibre as a transport fuel isn’t one of those uses. The fibre could be converted into liquid fuels, but that isn’t proposed at this stage.

This thread has evolved into sometimes esoteric discussions that vary from true alternative projects to academic exercises to fringe technologies to over the horizon what ifs as well as what is happening in the mainstream today.

Thanks for that @mark_m, and the more recent posts have indeed introduced new alternative and renewable fuels, although many of the details seem beyond consumer issues such as ‘what does this mean for me?’ regarding products, regulation, environment, safety, well being, and so on, all topics that Choice ‘is about’.

The .community was envisaged as a place for all Australians to get help with the products and services we use every day, and to have their voices heard so that we can have fair, just and safe markets for all.

Many interesting and informative topics have been raised across the forum including this one, and while not wanting to stifle other topics and issues of the day, this one will be closed as having been a robust and in-depth discussion that has well considered the topical issue. Thanks all.

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Since this topic is closed, a post has been on-moved to an open existing topic that is related. It was merged into: Solar and Grid Connections