Exotic Renewable Energy Plants: Tidal Energy


Tidal Energy power plants are definitely some kind of an exotic form for energy production. That’s because most tidal power plants are just pilot projects that are only build for research purposes and do not create a very big amount of energy in their lifetime. Tidal energy is one form of hydropower energy that gets obtained from tides and is then converted in useful electricity. In ancient times and in the middle ages tide mills have been used to mill grain, and nowadays axial or cross flow turbines are used to produce the electrical energy that is needed in modern times. As the gravitational attraction of the moon moves huge amounts of ocean water on certain coastlines or trough lagoons, tidal power plants were build in this strategic positions, there are 4 main types of tidal power generators: Tidal stream generatorstidal barragesdynamic tidal power and a tidal lagoon.

Unfortunately the issues that come with tidal energy are fairly big, from environmental concerns on marine life (also given the danger of blade strikes and the acoustic output). From a technical and maintenance point of view corrosion in salt water and fouling have a big impact on the plants and make them hardly economically efficient.

Even tough there are some massive problems to face when it comes to significant tidal power generation, there are some steps in the right direction, like a 3,4 MW tidal power generator in the East China Sea.

Check out tidalenergytoday.com for more news on the argument!


Paris Summit 2015 – Each country’s pledge


Carbon Brief has been following each country’s pledge towards the Paris 2015 summit. Here on this post you will find more details on how each country pledged in the upcoming summit. While for some countries, the pledges seem a big task however it will be interesting to see if they manage to achieve the target.

For instance, Mexico – the first developing country to come forward – includes a section on adaptation, while the EU is silent on the topic. Switzerland’s pledge of a 50% reduction in greenhouse gas emissions looks high compared to the EU’s “at least 40%”, until you realise they plan to use international carbon credits where the EU will make all reductions on home soil.

These pledges are also known as “intended nationally determined contributions”, or INDCs. You can find more details of each country’s INPC on UNFCCC. If the INDCs fall short – as they are widely expected to do – there is no official mechanism in place to ratchet them up before Paris. This is where they will be incorporated into the agreement, and likely take on some element of legal force.

I have my skepticism too but let’s wait for this event to happen!

Source: Carbon Brief

Wind Hybrid Power System


Few days ago my colleague and a friend Max wrote a piece about Wind to hydrogen possibility. It was an interesting article.
It got me thinking about other possibility so in this post, I am going to write some different ways of creating energy and storing through Wind/Solar.

Hybrid power describes the combination of a power producer and the means to store that power in an energy storage medium. In power engineering, the term ‘hybrid’ describes a combined power and energy storage system.Hybrid systems, as the name implies, combine two or more modes of electricity generation together, usually using renewable technologies such as Solar Photovoltaic (PV) and wind turbines. Hybrid systems provide a high level of energy security through the mix of generation methods, and often will incorporate a storage system (battery, fuel cell) or small fossil fueled generator to ensure maximum supply reliability and security. As you can see it from the image above.

From coal usage we generate almost 50% pf pollution so using Wind energy is very very sustainable.

Let’s look at various like of Hybrid Power Systems.There are five kinds of Hybrid Power system. We will see a brief overview of each hybrid system.

1) Wind-Hydro system
2) Wind- Hydrogen System
3) Wind-Diesel System
4) Wind Compressed air system
5) Wind – Solar System

1) Wind-Hydro System – It generates electric energy combining wind turbines and pumped storage. Wind-hydro stations dedicate all, or a significant portion, of their wind power resources to pumping water into pumped storage reservoirs. These reservoirs are an implementation of grid energy storage.

2) Wind-Hydrogen System – One method of storing wind energy is the production of hydrogen through the electrolysis of water. This hydrogen is subsequently used to generate electricity during periods when demand can not be matched by wind alone. The energy in the stored hydrogen can be converted into electrical power through fuel cell technology or a combustion engine linked to an electrical generator.

3) Wind-Diesel System – A wind-diesel hybrid power system combines diesel generators and wind turbines, usually alongside ancillary equipment such as energy storage, power converters, and various control components, to generate electricity. They are designed to increase capacity and reduce the cost and environmental impact of electrical generation in remote communities and facilities that are not linked to a power grid. Wind-diesel hybrid systems reduce reliance on diesel fuel, which creates pollution and is costly to transport.

4) Wind-compressed air systems – At power stations that use compressed air energy storage (CAES), electrical energy is used to compress air and store it in underground facilities such as caverns or abandoned mines. During later periods of high electrical demand, the air is released to power turbines, generally using supplemental natural gas.Power stations that make significant use of CAES are operational in McIntosh, Alabama, Germany, and Japan. System disadvantages include some energy losses in the CAES process; also, the need for supplemental use of fossil fuels such as natural gas means that these systems do not completely make use of renewable energy.

5) Wind-solar systems –

5.1) Wind-solar building – The Pearl River Tower in Guangzhou, China, will mix solar panel on its windows and several wind turbines at different stories of its structure, allowing this tower to be energy positive.

5.2) Wind-solar lighting – In several parts of China, there are lighting pylons with combinations of solar panels and wind-turbines at their top. This allows space already used for lighting to be used more efficiently with two complementary energy productions units. Most common models use horizontal axis wind-turbines, but now models are appearing with vertical axis wind-turbines, using a helicoidal shaped, twisted-Savonius system.

solar wnd turbine

If I missed some kind of Hybrid Power system, you are welcome to comment or suggest further.

Source: Wikipedia

Wind-to-Hydrogen: A possible solution to store energy?


If you follow our blog than you might know that one of the topics we discuss most is how to create energy in a sustainable way and how we can store that energy.

When electricity gets produced it has one big disadvantage: it has to be consumed when it gets produced. It is very difficult to store energy in big quantities. One possibility for the future could be what we discussed in one of our previous blog entries (HERE: Tesla lets you store energy at home) storing energy in a decentralized way.

Pumping water to higher places and use it when most needed is another way. But here i show you something even better: Using wind power to create hydrogen. In this article from derstandard.at, my favorite Austrian newspaper.

In a pilot project in Niederösterreich wind power gets used to create hydrogen trough electrolysis. Hydrogen is a high energy fuel, that can be used in different ways to get stored and then reused for energy production. The station build can produce up to 31 kg of hydrogen a day, consuming 50 liters of water/hour.

Right now the gained hydrogen can also be used to get mixed in the conventional natural gas pipelines, that allow a percentage of up to 5% mixture. But also cars could be powered with hydrogen.

The security aspect is not more difficult to handle than with other comparable substances. Hopefully this project shows that this is a way that has a bright future. Applied on a big scale this could be a realistic way to gain in energetic independence and in energetic sustainability.

Biogas, the underrated renewable energy source!


Renewable energy sources are becoming crucial for a sustainable energy supply in the next decades; the only way to reach more independency from fossil fuels is a good mix between all the different possibilities that we have as solar, wind, water, and geothermal power sources.
But one source is quite often forgotten: Biogas from Anaerobic Digestion! There is so much potential in it, and its exploitation on a big scale has only begun.
Lets take a closer look on anaerobic digestion. In a process where microorganisms break down biodegradable material in the absence of oxygen gases like methane are produced. Exactly this gases can then be used in a second step to produce electric energy, to heat buildings and even to power cars! Amazing, dont you think so?
But you may ask, what happens to the solid remains called digestates. Well the answer is simple, they are used usually as fertilisers in agriculture.

When it comes down to pros and cons, here are the major aspects:

+ Sustainable and local energy production
+ Raw material supply locally
+ Co2 balance friendly
+ very good storage possibilities (!)
+ good for decentralised energy supply, also in rural areas

– Farmers tend to produce plants for energy production purposes
-high costs to construct a biogas production site
-gases are highly explosive and therefore dangerous

For some further insight I consider you to google the topic, you can find some super interesting articles on biogas. This post was just meant to make you aware of what anaerobic digestion is and how we can use it for energy production!

Keep tuned for more posts on this argument (it is definitely one of my favourite ones 😉

Energy Seeping Ignorance


Few weeks ago my friends and I were talking about electricity saving and I mentioned that my ex-flatmate used to leave this TV light on all the time. I mean he would switch off the TV but not completely off from the plug or his mobile charger was always plugged even though the phone wasn’t charging. It kind of bothered me but I ever said anything since I felt it might be privacy intrusion. However, that evening when I was discussing about this with my friends, a guy in the group ( he is studying Mechanical Engineering) spoke how in terms of money it doesn’t cost that much. I agreed with him since he presented his reasons well but it made me more curious about how much electricity we waste or how much in total we actually waste in terms of money.

So after I made few research on internet about it. I came up with this Stanford Magazine article about exactly what I was looking for.


It’s called vampire energy where because of our small ignorance we waste few bucks. In the paper, you will see that for each appliance left with electricity on, how much energy we will eventually waste.
For example, usually we spend 11 cents per kilowatt an hour ( so technically my friend was indeed right). However, leaving it on stand by mode will eventually cost us a lot.

In the paper you would see an image where you can find more details about various appliances usage while it’s on and while it’s on ‘stand by’ mode.

A fully charged cell phone plugged into the wall is consuming about 2.24 watts, or 60 percent of the power it consumed while charging. Even worse is a charged laptop that’s still plugged in, which consumes 29.48 watts, 66 percent of the 44.28 watts consumed while charging. If you left it plugged in all year, it would consume as much electricity as running your coffeemaker for 12 days straight.

The numbers might seem small but they still matter a lot overall. Why don’t we start from today? Lets switch off completely an appliance when we are not using it. Not only it will be a good news to our financial conditions but we will be happier consciously.

Tesla revealed batteries for your home


For sure you heard about Tesla, the US American producer of the very successfully selling electric car Tesla Model S. And if you find their revolutionary approach in the car sector as interesting as I do, you will definitely appreciate the latest news from Tesla.

On April 30, they announced at a press conference in Los Angeles that they will sell their most innovative battery system also separately for consumers. They will sell their battery packs that will cost around 3500 $ and are able to store 10kWh,


Now you may ask why should I buy a battery for my home? Obviously the battery can supply you during a blackout but it is not directly ment for that. The main reason to get one is that if you have an external power supply, for example solar plants you can storage energy efficiently (which was not that easy and cheap before) or you can charge it during the time of the day when energy costs less and use it later!

What do you think about Teslas idea? Discuss below!