Heating with wood pellets is the convenient, reliable alternative to fossil-fuelled heating. So long as you don't run out of pellets…
If you order too early, you are increasing your cost and inconvenience. If you order too late, you are going to go cold.
So how do you know when to re-order?
If you've got a wood-pellet system, you will know it's not as easy as you'd think.
You've gone for the convenient renewable-heating option. Do you really want this to be your problem?
Why not let us take the responsibility? We can monitor your fuel usage and schedule your next delivery for the most suitable moment.
Level sensors for your wood pellet store
For us to monitor your fuel level, you will need to install one of the fuel-level monitoring systems on the market, and give us access to the data.
The original system is the Mesima (formerly DELOX) system. This measures the way that the capacitance of a pair of electrodes in the store changes with the level of the pellets. It is one of the few systems that makes a direct physical measurement. That makes it more accurate for some types of store, such as trough silos, where there is not a single point that a sensor can be pointed at to give a reasonable indication of the level. On the other hand, in some stores, the pellets do not flow out in a linear pattern against any practical alignment of the electrodes. The system is relatively hard and expensive to install in all stores, as it requires the installer to enter and work inside the store to install the electrodes. And the telemetry requires a good mobile signal.
Systems to measure the level by radio or microwaves used to be highly unreliable and inaccurate, because the inevitable dust in the store would confuse the sensors, and it was hard to find a point at which the sensors could be aimed that gave a reasonable indication of the fill level. However, these systems have been evolving and some manufacturers claim to have cracked this problem. The Schellinger Sonavis system is one such new entrant to the market in 2016, which claims to give accurate and reliable readings, without the installation cost and complexity of the Mesima system. VEGA Instruments have also been offering systems like this for years, although reports about the system's accuracy and resilience to dust remain mixed.
Neither of the above types of monitoring system are cheap, nor are they practical for all stores. For instance, none of them is suitable for fabric silos. You may prefer to go for a cheaper option like the ISTA system, which measures the heat output from the boiler and converts that to an estimated fuel-consumption figure. This approach is also an option on some types of boiler (e.g. ETA). This is vulnerable to cumulative errors, as the assumed efficiencies may not be accurate. But this risk can be minimised by resetting the fill level each time the store is refilled.
Inclusive wood-pellet supply contract
If you install one of these monitoring systems and give us access to the data, we will give you a fixed, inclusive price per tonne, so it makes no difference to you whether we deliver one tonne or twenty. And we will give you a guarantee not to let you run out, so long as the monitoring system gives a reasonably accurate and current indication of the fill level.
If we can monitor your fuel level, we can more easily fit your deliveries with other customers in your area. We will take account of this logistical benefit in the fixed price that we offer you. You get the convenience and security, and we get the efficiency.
You may not be able to justify the cost of a monitoring system. In that case, we can offer two alternatives that require no investment or commitment:
- So long as you only buy from us, we will use your historical consumption data, the capacity of your boiler and your store, your last delivery date and size, and average degree-day data for your region (to allow for seasonal variation) to estimate when you are likely to run out. This estimated date is visible to you and us, next to the chart of your deliveries on our Customer Portal. It is not reliable, because your usage and the weather may vary from the historical average. But it may serve as a useful reminder of when you should expect to pay more attention to your fuel level.
- You can ask to be considered for our top-up service. We will notify you if our truck is in your area with some spare capacity onboard, and you can request to be allocated some of that spare fuel. We offer a flat price that is significantly cheaper than a scheduled small delivery to your area. You pay the same amount per tonne regardless of how much we are able to deliver or you are able to take. We give no guarantee to deliver any particular quantity, and you are under no commitment to take any particular quantity. If you are in an area that we visit frequently, which applies to large parts of the country (given our national coverage), this option may allow to to keep your store topped up at low cost.