News / knowledge base
The Netherlands as a developing country?
Distribution of energy has always been challenging in developing countries, but at the moment this is becoming a major problem in the Netherlands as well. There is very limited space on the grid for the feed-in of sustainably produced energy, which means that solar and wind energy installations can not be built or are connected to a limited extent while waiting for a grid connection. In other cases, it is not even possible for companies to be connected for several years! Is the Netherlands becoming a developing country in the field of energy?
Sun & Wind Factory was already active in the early years of this century in building off-grid systems with solar and wind energy in developing countries such as Madagascar, Kenya and Senegal, at the time to reduce the costs of diesel generated energy or to become independent in terms of energy supply. Telecom installations, lodged, companies and entire villages were provided with locally generated solar and wind energy with battery systems and smart control devices to keep supply and demand in balance. We can therefore use our many years of experience from these countries to install reliable energy systems here to avoid the problem of 'congestion' (accumulation of blockage of a network). On the other hand, this now provides an opportunity to further develop our proven off-grid systems for optimal operational reliability and independence in order to guarantee continuity in these turbulent times. Want to know more? Please contact us for tailormade advice.
How do solar panels work?
Solar panels convert sunlight into electricity. A solar panel contains silicon solar cells that convert light into direct current. This direct current (also referred to as DC) is then transported via electronic conductors to the inverter, which then turns it into alternating current (AC). The generated power (AC) can then be used directly by electrical appliances, fed back into the energy grid (netting) or stored in a battery system.
What does watt-peak mean?
The term watt peak (Wp) refers to the power of a solar panel. It is a measure of the capacity of photovoltaic cells (of the solar panels) to convert solar energy into electricity.
How does peak load shaving work?
The energy consumption of a household or company almost always varies during the day. For example, in a company there is often a peak in the energy usage in the morning and in a household in the evening when there is cooking and people are at home more often. Reducing these peaks is called peak shaving. The energy generated during sun hours is stored in a battery pack and used later during peak times. The energy generation system (grid) will be less heavily loaded and therefore, the energy costs will be lower.
How does net metering work?
With a standard PV system, a household will run directly on the electricity generated by the solar panels during the day. If you need more electricity than your own system can generate at that time, the energy company will automatically assist you: you will receive extra electricity from the grid. When more electricity is generated by your solar panels than necessary, it is automatically fed back into the electricity grid (at the current electricity rate of your supplier, which can therefore fluctuate). The net functions as a battery in a grid-connected system. This is called net metering.
As of 2014, a net metering limit applies in the Netherlands, which is different for everyone. It is the amount of energy that you have received from the energy company. In the calculation for netting this amount of energy applies as a limit. In this way, you can never balance more than the amount of energy that you have supplied. It is therefore not advisable from a financial point of view to install more solar panels than you need to generate your own annual power consumption. To ensure that the current is actually settled, the flow meter must be able to turn back in the event of a negative power consumption. It is therefore essential to check whether you have a suitable meter. Net metering makes it very attractive as a private individual in the Netherlands to invest in solar panels. Thanks to the 1-to-1 settlement, you can recoup your investment by net metering in an average of seven years. It has been announced that net metering will be phased out from 2023. For the most up-to-date information about the scheme, keep an eye on the website of the National Government.
What is MPPT?
MPPT stands for Maximum Power Point Tracker. With the MPPT, the inverter determines the ideal voltage (Maximal Power Point) with which the yield from the solar panels can be maximized. There must be an optimal ratio between the current and voltage, this differs per type of solar panel and is also subject to changes in temperature and light. An inverter with a good MPPT can therefore always get the most efficiency from the solar panels in changing weather conditions.
How does a hydrogen fuel cell work?
The smart off-grid systems we design and install mostly contain the primary renewable energy sources solar and/or wind. To cover the energy demand during less sunny and windy seasons is always the main challenge during the engineering process, for which we use different kind of battery storage systems. Depending on the local situation and project requirements it ranges from lead-acid, AGM, Lithium to salt water storage solutions. In certain off-grid application (especially off-shore) battery storage is however not sufficient to provide stable power year-round, which requires an alternative energy source. Sun & Wind Factory has already long term experience in fuel cells using (Bio)Ethanol as a steady source of energy for small scale systems. The hydrogen fuel cell is a logical continuation and a nice addition to a solar / battery system that can provide a stable energy input. When insufficient energy comes from the solar panels and the wind turbine and the battery voltage no longer provides sufficient energy, the hydrogen set can take over the energy production. When the solar panels and wind turbine produce energy again, the hydrogen set will turn off in order to ensure the greatest possible autonomy. This clean, quiet and affordable fuel cell only emits water and is a reliable and sustainable alternative to additional batteries or a generator.
Does it help to think about my planned energy consumption?
A solid planning of your expected load is always very important for the design of an off-grid autonomous energy system. How many electric devices do you want to connect to your independent energy system? How often and how long do you use these? And are all loads crucial? All important questions which will help us in making an accurate off-grid system calculation for your situation.
Is it possible to use a combination of wind and sun energy for off-grid energy systems?
In most situations it is possible to use a combination of wind and sun together in an off-grid energy system. Depending on the location, budget and situation we will give tailor-made advice about the best sources of natural energy. For wind energy it’s important that the location is situated in an area with a lot of wind streams and not in an area with a lot of trees. For solar systems it’s important that the site is easy accessible for sun radiation. Clearly, the amount of sun hours on a location is also of great significance. With special software programs we can check the quality of natural energy sources at your location.
What is a mini-grid?
The term mini-grid (also referred to as microgrid) is used for isolated energy grids for small-scale electricity generation (10 kW to 10 MW) which are not connected to a public energy grid. There are mini-grids for villages, agricultural-, commercial- and industrial applications. A mini-grid can supply a limited number of users with energy via a linked distribution network that can function independently of the energy network. The sustainable generated energy (sun or wind) is either supplied directly to the users or stored in a shared battery pack. The advantage of a mini-grid compared to a stand-alone system is that it has a greater power, so it is very suitable for companies looking for more renewable energy.
What is the difference between a mini-grid and a smart grid?
A smart grid is a two-way electricity system that can transport energy and communicate through internet. Online communication makes it possible to enhance supply and demand. This causes fewer peaks in the electricity grid. A smart grid consists of controllers, computers, telecommunications and other devices that communicate with each other. These technologies also communicate with the grid to respond to changes in the electricity grid. The difference between a mini-grid and a smart grid is the communication between the electricity components. All components of a smart grid are connected to each other via the internet, which means that we can respond quickly to supply and demand. There is no standard online communication within a mini grid. The energy generated can be used directly or stored in a local battery pack.
What is the difference between an off-grid system and a self-consumption battery system?
In most cases an off-grid system is not connected to a public grid and sized to provide all energy for the total system in worst case situations. A self-consumption system has been designed to store energy which has been generated during the day to store for usage at a later time when there is less solar and wind generated energy. A self-consumption battery system is usually connected to a public grid. Normally the battery technology and inverters in an off-grid energy system and a system for self-consumption are different. Always contact an expert for advice for your specific energy system.
Is an off-grid energy system with battery storage the same as an UPS system?
No, off-grid energy storage systems are sometimes used as a UPS system but are not the same. An UPS (Uninterruptible Power Supply) ensures that emergency power is available in the event of an interruption of the main power line/power failure. In the event of a grid interruption, a UPS system immediately takes over the power supply and ensures that the connected systems continue the supply. It is therefore mainly used in critical applications where there must be security of power supply; for example at hospitals, data centers, factories or telecom networks. An off-grid storage system is designed for maximum self-consumption, so the battery may be empty when you need it unexpectedly. A UPS system is only used for the emergency power supply and will therefore always be fully charged. However, a combination can be made.