Ask HN: How to utilize excess energy in remote areas | Hacker News Reader

Ask HN: How to utilize excess energy in remote areas

15 pointsl7l19 comments

For example if you have a large area in the desert that is not connected to the power grid, but has the potential to generate electricity. What could be profitable?

View on HN

My father has a small house in southern Spain. There's no grid so we put loads of solar panels (8kW). In summer, there's plenty of energy.

I have installed 3 servers (a "normal" tower PC + graphic card) running Boinc. A small timer powers on the PCs at 10, and powers them off at ~17h. Once up, they start folding and calculating for Folding@Home or WorldCommunityGrid.

I don't earn any money from it, but I like the fact that I'm contributing to science

I’m so glad you didn’t say mining crypto.

I find this question to be quite flawed. We perpetually fail to consider that forming the grid is a real-time interconnected machine. There isn't really any excess energy, unless you are storing excess energy (e.g., in batteries, etc.). Otherwise, because we're working in power, you're just not generating what you're not using. That's the concept of spinning reserve, you're just not running full-tilt: https://en.wikipedia.org/wiki/Operating_reserve

If we insist on answering the question as-is: if you have a big area with large potential to generate electricity, just build the power resource and connect it to the grid, and bid on the local real-time & futures power market in your interconnection region. If the numbers don't look good for you, maybe you can mine crypto, but in reality you'll actually get a better return on your investment by investing in energy storage and playing the market with your generated energy to shift its use to peak times on the grid.

This isn't the answer that people are suggesting, because it's not glamorous.

On a smaller scale, I’m on off-grid solar and I potentially have 20kWh excess generation a day on solar (+/- 100%). Any exciting ideas regarding what I could shove that into?

Time shifting of existing needs is probably the most effective use.

Do you have hot water storage? Time it to run down and recharge when you have excess. There are commercial products that do this semi-automatically. You can also get hot water taps that replace tea kettles that work on a similar principle.

If you have air-con or electric heating then run it to store heat and/or cool in a thermal mass.

Organise your day to run washing machines etc. at those times.

Phase change of water to ice can shift cooling loads if you have warm nights.

Plus electrify anything you have that currently burns fuel.

I'd love to see way more effort and subsidies going into thermal batteries. We don't need to invent any new technology since it already exists. Thermal batteries can use pretty mundane, low impact materials, so the downsides of mining and manufacturing scale of chemical batteries don't apply. Thermal batteries can't solve the problem on their own, but we can build them now at huge scale pretty cheaply.

In order of impact (since you say you're off-grid which implies you have batteries or storage):

1) Get an EV if you don't already have one: 20 kWh is about the perfect excess capacity to convert.

2) Upgrade fossil-fueled appliances in your home to electric appliances, like to induction cooktops and heat pumps. (Do you have a gas range? They're so poor at heating efficiency and pollute your living space.)

Disclaimer: This suggestion is not a cheap idea though perhaps something to think about. As a matter of water storage and preparation, one could use solar power to pump water into one or more elevated water tanks during the day then let it run into a ground level or underground tanks at night passing through some turbines. There are some hobbyists on youtube that do this and produce between 500 and 2000 watts continuous, depending on volume and flow rate. This is may be useful if your power consumption is higher at night. Some math should be done in advance to determine the volume of water required to sustain the desired flow rate for most of the night and to determine the size and number of tanks and of course the overall cost.

There is likely no harm in keeping extra water around for the rule of 3's. [1]

[1] - https://www.trailhiking.com.au/safety/survival-rule-of-three...

You could boil water to use it as an alternative to chemicals for dealing with weeds.

>Any exciting ideas regarding what I could shove that into?

May not be "exciting", but storing for future/dark use would be good :)

You could sell it by opening a charging station. People would love to charge their cars with solar energy.

Interesting! Perfectly fits my question.

Carbon Capture and Hydrogen Electrolysis will make Syngas (methan + CO ) Which can be formed into multiple organic compounds (fuels, etc) It seems like the capital costs is something like $0.75 per gallon of gasoline on a respectable scale. (skylon study). The electrical cost is where the real cost of synfuels.

Or, on a small scale, you could charge an electric car. :)

Electrowinning scrap metals to purify them? Electric kiln for pottery? Crushing rocks into gravel?

As renewables drop in price, the connection becomes a greater part of the cost.

I don't think this will make long term sense as a result.

You really want places with sun, and wind, and good grid connections to industry with power needs to make the most of the opportunity and then you can make green hydrogen to export as well, but that also requires good transport connections.

That export opportunity currently depends on legislation though as current alternatives beat it on price if they're allowed to ignore their externalities.

Power to Gas. Use the electricity to make hydrogen and then ammonia. You will need water though…but not that much.

Today that’s probably not very practical. But maybe in 5 years…

Melting and mining nearby resources.

Renting out remote controlled streaming geofenced battery charging model cars.

Autonomous radio telescope.

Mining crypto. There's no issues with burning energy that would otherwise go to waste anyway.

Reply on news.ycombinator.com