Guest post by Emma Metson*
Off-grid energy sources are those that are not connected to the electricity grid. They’re also called stand-alone power systems which generate electricity using renewables. Perfect examples of renewables are hydropower, solar, wind, geothermal, and biomass.
According to the Department for Business, Energy and Industrial Strategy, nearly a third of the UK’s electricity between April and June was generated from renewable sources. This was a new record compared to last year at around the same period.
Accenture’s research, on the other hand, predicted that 11% of Europe would become off-grid by 2035. It may not look like much, but that’s a huge progress and a milestone in itself. That is considering how much we’ve depended on coals and fossil fuel since the industrial revolution.
Of course, only time and innovations in technologies used to generate power from these sources will decide if the prediction will come true.
Here’s a rundown of the pros and cons of the top, most popular off-grid energy sources offer.
Without a doubt, the energy that we get from the sun is one of the cleanest, most sustainable, and most renewable sources that we can ever find. This energy supply is so abundant that one hours worth of the sun’s energy can supply the whole requirement of the planet.
Unfortunately, we’re only able to harness .001% of this energy. A big part of the reason why this is the case is the cost that’s involved in installing solar panels, rendering it unreliable. However, these obstacles have already been surpassed in recent years.
If you’re looking to go off-grid through solar, you’d probably have to invest at least £5,000 if you have a household of at least three people. That’s a lot of money but consider this: in 2010, buying a solar system that can power the whole house would have cost you at least £15,000.
As you can see, we’re headed in the right direction to making solar more accessible.
- It a great source of renewable energy.
- Solar can significantly reduce utilities and in some cases, removes your dependence on mains as your power source.
- Low maintenance.
- Can be used for different applications.
- Bound for further technological improvements which means you can expect more from solar power in the future.
- The initial investment is still expensive.
- The efficiency of solar panels is weather-dependent.
- Solar panels need a lot of space.
- Slightly associated with pollution especially during transportation and installation because of the greenhouse gases emitted.
- Batteries used to store solar energy are also expensive.
Harnessing the gravitational force of flowing water and converting it to electricity — that’s what hydropower is all about. Electricity is produced using a downwards flow of water from higher ground.
Interestingly enough, hydropower was called ‘white coal’ due to the massive amount of energy it can produce on top of a seemingly infinite source. In fact, it is one of the oldest and cheapest methods of generating power.
The British Hydropower Association states that this energy source currently produces 17% of the world’s electricity. In addition to that, hydropower accounts for 90% of the world’s renewable energy sources.
But like anything else, hydropower has its pros and cons.
- Clean and safe.
- Cost-effective in the long run despite the high initial investment.
- Flexible as hydro plants can be scaled up and down quickly depending on the energy demands.
- Suited for industrial applications.
- Contributes to the economic growth of remote areas
- Contributes to methane emissions due to plants rotting in an anaerobic environment in flooded areas.
- Ecosystem damage, specifically in wetlands. Since turbine gates are often opened intermittently, it affects the natural flow of water. This can have a significant impact on animals and plants living in the area
- Risk of floods and droughts. Strong water currents may cause flooding and people living in the downstream area can be extremely vulnerable to this. Hydro plants risk cause droughts in the local area.
- High upfront costs.
Britain has 40% of Europe’s wind resource — that’s enough to power the whole country several times over. Wind energy is clean, free, safe, and it’s something that will never get depleted.
Over the years, the technology has improved so much that both on and offshore wind power is now possible. Modern wind turbines are now able to efficiently and effectively convert wind power to electricity.
The benefits of wind power are obvious but here’s a more detailed breakdown of its pros and cons.
- Environmentally friendly
- Wind power can provide electricity to areas that are off-grid.
- Technology is becoming more affordable.
- Low maintenance and running costs.
- Building wind turbines creates jobs.
- The wind can sometimes be inconsistent. While it’s true that it will never run out, there’s always a chance that the wind will die down which affects or halts production.
- Expensive installation
- Noise pollution. Although wind energy is environmentally-friendly, a single wind turbine can be heard from hundreds of meters away. Combined with multiple turbines and the result is angry homeowners.
- It’s a threat to wildlife like birds and bats.
Geothermal energy is the heat that’s generated and stored in the Earth. The most perfect and straightforward example of geothermal energy is hot springs. Nowadays this energy is being harnessed to produce electricity and provide warmth to homes.
Geothermal energy is naturally occurring in the UK. In fact, Southampton city council has been operating a geothermal power station since 1986. This provides heating for different places like the city hall, superstore, the port of Southampton, and the swimming centre.
Not only does it provide heat and electricity, but it also has cooling functions. That’s mainly because of the insulating properties of our planet. A good example is during summer where a geothermal system pulls heat from your house. It carries it to the ‘earth loop’ and deposits it to the cooler part of the earth.
- It has heating and cooling functions.
- It’s free and available almost anywhere.
- It’s now more affordable.
- Requires little to no maintenance
- Although geothermal basins are widely spread, resources vary from region to region. The problem lies in the fact that this type of energy cannot be transported. This means that only those who are near the source can benefit from it.
- Huge investments are needed to build exploration sites.
- Can cause minor seismic activity. This happens when high-pressure water is injected into the ground to produce steam.
- Time-consuming because a lot of research and explorations need to be done first to determine if an area is feasible.
Biomass is organic material that comes from plants and animals. It contains stored energy that comes from the sun through photosynthesis. The chemical energy in biomass is released as heat when it is burned.
Here are some examples of biomass and their uses:
- Animal manure and human sewage – can be converted to biogas and burned as fuel
- Food, yard, and wood waste in the garbage – generate electricity in power plants through burning or converted to biogas in landfills.
- Wood and wood processing wastes – burned to produce electricity and is used to heat buildings as well.
- Crops and waste materials – burned as fuel or converted to liquid biofuels.
- Cost effective as most materials are from leftovers from wood.
- The carbon dioxide that’s emitted during the burning process is equivalent to the amount absorbed when growing trees.
- It supports local economies.
- Easy to store and produces small amounts of ash.
- Wood pellet boilers are expensive.
- The boilers require frequent maintenance.
- Storage of biomass fuel needs to be considered carefully. It needs to remain dry. Otherwise, it will not burn efficiently.
Off-grid energy sources are indeed starting to take over in popularity from coals and fossil fuels. It will only be a matter of time before people can become truly free from grid power lines.
There is still a lot of progression to be made in renewable energy, but if what we’ve already achieved is anything to go by, we’re getting closer to greener sources.
Until then, all of us need to look at how we’re consuming energy, and ways we can lessen our environmental footprint in our homes and day to day life by using energy efficiently and wisely.
*Please note that the views are that of the author, not necessarily that of en-form.