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Brazil Hits 92% Renewable Energy Milestone

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Re: Brazil Hits 92% Renewable Energy Milestone

#11

Post by gchamonlive »

dheera wrote: post #7

While it's good for the power grid to be mostly renewable energy and it may be a great milestone, let's not forget that without conversion of vehicles to renewable energy Brazil is still running its total energy requirements mostly on fossil fuels.

That is untrue. 27% of gas is ethanol, and virtually all cars run on both gas and ethanol. Trucks use diesel, sure, but the amount of cars running on ethanol is not negligible. So while you would still need to renew the automotive fleet to electric vehicles to tap into that, Brazil is already using renewable fuel sources for cars.

Not to mention that converting all cars to electricity will put more pressure on the electric distribution infrastructure which in itself will require more investments and will cause environmental impact invariably.

Re: Brazil Hits 92% Renewable Energy Milestone

#12

Post by cassianoleal »

dheera wrote: post #7

While it's good for the power grid to be mostly renewable energy and it may be a great milestone, let's not forget that without conversion of vehicles to renewable energy Brazil is still running its total energy requirements mostly on fossil fuels.

I don't know the numbers but I don't doubt diesel for trucks makes up a lot and perhaps most of the energy consumption in the country.

Thankfully, the federal government seems to be taking notice and railways are a priority for the new PAC [0] (_Programa de Aceleração do Crescimento_, or program for growth acceleration).

It's not much but it's a start.

[0] https://www.gov.br/transportes/pt-br/assuntos/noticias/2024/...

Re: Brazil Hits 92% Renewable Energy Milestone

#14

Post by adgjlsfhk1 »

gchamonlive wrote: post #11
dheera wrote: post #7

While it's good for the power grid to be mostly renewable energy and it may be a great milestone, let's not forget that without conversion of vehicles to renewable energy Brazil is still running its total energy requirements mostly on fossil fuels.

That is untrue. 27% of gas is ethanol, and virtually all cars run on both gas and ethanol. Trucks use diesel, sure, but the amount of cars running on ethanol is not negligible. So while you would still need to renew the automotive fleet to electric vehicles to tap into that, Brazil is already using renewable fuel sources for cars. Not to mention that converting all cars to electricity will put more pressure on the el…

ethanol produces more emissions than regular gas. the only thing ethanol is good for is as a farming subsidy.

Re: Brazil Hits 92% Renewable Energy Milestone

#15

Post by cogman10 »

soperj wrote: post #10
DavidKarlas wrote: post #8

Earlier quoted context omitted.

Isn't this just cycling carbon in ecosystem? Same as planting tree on 100 year scale is pointless... I would imagine that hydro is ~neutral on 100 year scale, while coal is not, since we introduce carbon into ecosystem. What am I missing?

Produces methane, not CO2 because the plants decompose in an oxygen free environment. Because of the cycling of water throughout the year, during the dry seasons plants grow along the shoreline (which varies considerably because of the use of hydro), and then are covered up during the rainy season. This can be hundreds of kms every year.

Methane isn't great, but unlike CO2 is has a pretty short lifetime in the atmosphere (just 12 years). So the impact of the methane release from hydro is basically static rather than an ever increasing problem.

Re: Brazil Hits 92% Renewable Energy Milestone

#17

Post by cma »

adgjlsfhk1 wrote: post #14
gchamonlive wrote: post #11

Earlier quoted context omitted.

That is untrue. 27% of gas is ethanol, and virtually all cars run on both gas and ethanol. Trucks use diesel, sure, but the amount of cars running on ethanol is not negligible. So while you would still need to renew the automotive fleet to electric vehicles to tap into that, Brazil is already using renewable fuel sources for cars. Not to mention that converting all cars to electricity will put more pressure on the el…

ethanol produces more emissions than regular gas. the only thing ethanol is good for is as a farming subsidy.

Corn ethanol end to end does, but does sugarcane ethanol in the tropics?

Re: Brazil Hits 92% Renewable Energy Milestone

#18

Post by cogman10 »

soperj wrote: post #9
krunck wrote: post #4

Earlier quoted context omitted.

Uh, no. Nowhere in that article do they mention coal. Not do they do not do a comparison of hydro plant and fossil fuel plant emissions per megawatt-hour generated.

https://en.wikipedia.org/wiki/Balbina_Dam "As a result of the methane released from its vast reservoir, proportional to its output, the Balbina Dam emits ten times more greenhouse gases than a coal plant."

This is going to depend very heavily on where the dam is placed. Balbina is particularly bad because it sunk a ton of organic material with a bunch of acreage taken up.

Almost a worst case for a dam really.

Re: Brazil Hits 92% Renewable Energy Milestone

#19

Post by bryanlarsen »

Qem wrote: post #2

Most of it is hydropower. But most good hydropower sites are already tapped, so we shouldn't expect this source growth to keep pace in the future. So, to keep these numbers good, it's necessary to crank up the deployment of solar panels and wind turbines a lot. Also solve the deforestation problem for good, otherwise Brazil will shoot its own feet by causing deforestation-induced droughts to decrease available hydrop…

Brazil is sitting in a pretty optimal position, though. Solar & wind is currently by far the cheapest energy source, if you can deal with the intermittency. And with so much hydropower, Brazil can slow down hydro power when the sun is shining and speed it up when it isn't.

You usually need to maintain flow in your rivers so you can't shut dams down completely and use hydro as pure storage, but the ratio of storage:generation on a dam can be adjusted.

Re: Brazil Hits 92% Renewable Energy Milestone

#20

Post by feedforward »

soperj wrote: post #3
Qem wrote: post #2

Most of it is hydropower. But most good hydropower sites are already tapped, so we shouldn't expect this source growth to keep pace in the future. So, to keep these numbers good, it's necessary to crank up the deployment of solar panels and wind turbines a lot. Also solve the deforestation problem for good, otherwise Brazil will shoot its own feet by causing deforestation-induced droughts to decrease available hydrop…

Not to mention some of it's hydropower is dirtier than coal in terms of methane & co2 produced. https://www.newscientist.com/article/dn7046-hydroelectric-po...

It is not dirtier. In the first week of operation it is dirtier, but then at some point it crosses a threshold and becomes permanently less dirty. As that article you link to attests.
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