ENERGY STORAGE IN THE SKIBSTEDFJORD BUILDING

The SkibstedFjord Building at Nordic Folkecenter for Renewable Energy contains an energy storage installation that gives professionals and other interested parties the opportunity to see and learn about Victron Energy and our proposal for self-sufficiency with renewable energy sources in their own business / own home.

The installation, which includes solar panels, a wind turbine, batteries, battery chargers and three inverters, is set up in such a way that it is possible to see, touch, follow and understand the cabling, as well as possibly the software setup.

The new setup gives us the opportunity to advise and teach on a more practical level and it is needed, says data specialist Anker Mardal, who has taken on the coordinating role in the set-up:

“There is great interest in energy storage with batteries, from both professionals and private individuals who want to explore the possibilities of self-sufficiency – either in their own business or their own home – and now we can do more than just tell; now we can show how it can be set up and how it works, and this is of decisive importance for understanding and thus also the courage to invest in it.”

How it works

The installation consists of several parts:

  • A ground-mounted south-facing solar system of 3.6 kW and building-integrated solar panels of 3 kW, mounted in different directions
  • A small 600 watt wind turbine, Leading Edge LE-600, sponsored by VANNHANDEL
  • Spanish Cegasa batteries. The batteries are each 13.5 kWh and they are stacked, two pieces, so it’ will be’s 27 kWh in total. .
  • Two different Victron Energy battery chargers; SmartSolar mppt 150/70 and SmartSolar mppt 450/100
  • The inverter is Multiplus II 5000/48; three pieces – one for each phase
  • Computer

The energy from the solar panels and the wind turbine is directly charged to the batteries through two different battery chargers, SmartSolar mppt 150/70 and SmartSolar mppt 450/100.

Maybe one is not enough? Yes, indeed. But with this setup we have the opportunity to show the operation and size of both battery chargers. Briefly explained, the SmartSolar mppt 150/70 is smaller, cheaper and without a fan, and is used on systems up to 8 kW. SmartSolar mppt 450/100 has a fan, four separate inputs, it can cope with more shade and is for systems in the order of 8 kW to 14 kW approx.

The batteries also have a built-in BMS (battery management system), with which the Victron Energy system can communicate directly. The BMS is of great importance for optimal utilization of the batteries and their lifetime.

The inverter is a Multiplus II 5000/48 – and there are three units. One for each phase. Again, not a necessity, but since it’s with demonstration and teaching in mind as well as supply and operation of the entire SkibstedFjord Building, it therefore requires three phases.

The inverter has battery inverters, which allow the current to go both ways. This means that it is possible to charge from the grid, as well as supply power back – and supply emergency power to the SkibstedFjord Building in the event of a power cut.

The system is programmed to navigate based on the electricity prices, as well as take into account the varying electricity taxes we have in Denmark. On top of that, it is also possible to program it so that the weather forecast (sun) is taken into account and based on these parameters the power is bought, sold or balanced.

At Nordic Folkecenter, the energy storage system in the SkibstedFjord Building is linked together with the other systems to optimize our purchases and power consumption based on the current electricity prices.

The cost

The price of an energy storage system with batteries, quite generally speaking, is like when solar panels really made their entrance in Denmark back in 2011/12; they are still relatively expensive, but we also see that the price of both batteries and inverters is in what looks like free fall.

The market for these systems suffers from the fact that most sold systems of this kind have been developed and optimized for the market in the EU – and not for Denmark, where the electricity prices and taxes are somewhat different. But there are also other things that influence whether such a battery system makes sense here in Denmark, says Anker Mardal:

“You have to take into account when investing in systems like this that we in Denmark have a somewhat different solar radiation, and we have enormous amounts of cheap wind energy when it’s windy; then the electricity costs almost nothing. So you should at least be sure that the system you want to install is equipped with regulation based on the Danish electricity prices and taxes.”

The primary reason for these considerations must be found in the economy and the CO2 account:

“The fact that the system can be regulated on the basis of Danish electricity prices and taxes is of great importance for the payback period of the system as well as for the CO2 account; it’s about charging the batteries with renewable energy, such as wind and sun, even if you don’t have a wind turbine in your backyard.”

Another good piece of advice Anker Mardal gives is the possibility of using different battery types:

“You have to be able to use different battery types, and not just those that have the same brand as the inverter. This allows the battery capacity to be adjusted up/down later. If we continue to experience greater fluctuations in electricity prices, it may make good sense for a household or company to invest in larger battery capacity, so the power on the batteries can be used when electricity is expensive.”

That the energy storage system is compatible with different types of batteries must therefore be seen as an investment.

For example, many electric cars have what is known as V2P (vehicle to power), which can potentially transfer to the batteries.

The possibilities are many, the choice can be difficult, which is why it is important to do your homework before embarking on self-sufficiency of this caliber. On your own or with Nordic Folkecenter on the sideline.

Prices per 11/9-24

  • Solar cells, 8.6 kWp + installation = DKK 32.000 ~ €4.300
  • Solar charger, SmartSolar 250/100 = DKK 5.400 ~ €730
  • Batteries Cegasa Ultra 175 = DKK 37.000 ~ €5.000 (possibly + VAT)
  • Inverter Multiplus II 5000/48 = DKK 8.500 ~ €1.200
  • Cerbo GX = DKK 2.500 ~ €350

There is also a lot of cabling, installation and whatever else may be needed in connection with setting up the system. And Anker Mardal admits that the price looks high, but…

“If we compare with the investments people made in solar panels in Denmark back in 2012, what it cost and if we include the high electricity prices in the period 16-21 of the day and consider the concept of security of supply, then the price is already at a level where the investment has a good payback period – both financially and in the CO2 account – if it is set up correctly.”

Want to see it and learn more?

Anyone interested is welcome to come and see the energy storage system.

If you want a deeper understanding of the facility and possibly knowledge and skills to get it yourself in your home / in your business, then we offer introductory courses that give you just that.

The course is also for you who already have a Victron Energy system, but who want to learn more about the options you have.