Winter for 2015 Has Passed

Well another winter period has completed and as of 1 September we are heading into spring.

The three  months of winter have been the coldest months for many years with August being significantly wetter and colder than previous years.This is reflected in the lower than normal pv results for the period.
Likewise the core temperature plummeted as the system tried to keep the core to the 21 degrees it was set for.

The system has had a few frustrating issues of late with pressure being regularly lost in the solar water system. the pressure release system has coped with the events with no damage to the system but we are still endeavouring to find where the pressure is leaking from. This impacts on the ability to store heat in the core so hopefully will be resolved sooner rather than latter.

  




The core temperature fell to 20 degrees in July and has only just started to move back up. As we move into the fourth summer period for the system the expectation is that the core should get above 35 degrees by the end of this coming summer.



As indicated the level of power from the pv system in August is the lowest since the system was installed. Hopefully the long hot summer that is forecast will generate plenty of Kwhrs in the period ahead.

First Quarter 2015 Results

The first quarter of 2015 has produced a great January and February and slightly messy March but overall the results for the house and the systems are similar to previous years.

The core temperature peaked at the end of February at 32 degrees and has decreased slightly to 30 at the end of March. One assumes this means that the heat has spread into the core and has assisted in drying out the core so that it will be more receptive to heat gain in the future and the total cubic metre area has increased. Time will tell on that one.

 The photovoltaic system continues to produce steady and similar results from previous years.January is consistently the best month for pv output followed by February and then December. We are now up to just under 10MWhrs since turn on of the system.

January produced 385.7KWhrs which is the best month yet.

The third annual report has now been completed and is available on the site.

November Results 2014

Well its been two months since I updated the blog. The house continues to perform as expected and the core is once again building up temperature as we have had a fairly good spring with plenty of ultra violet light.

As you can see the core temperature is on the rise and has got to 27 degrees by the end of November. We are hoping that it will rise to about 34 -46 degrees by the end of the summer period and hence will nearly last right through the winter next year.

At the same time the amount of power being generated by the Photovoltaic system has had an excellent two months with both being significantly better than last year which was a poor year. 

During November there were 5 days with greater than 15kwhrs being generated compared with only 2 in October.

Roll on the rest of the summer.

August 2014 Results

We are now at the end of the winter period and have slipped into spring.

During the last month we generated 196 kWhrs of power with a maximum of 9.95 kWhrs on any one day and a minimum of 2.14 kWhrs. QWe had three days with less than 2.5 kWhrs generated.

Overall the power generated for the month was slightly down on the previous years as can be seen by the graph.

The good news is that from now on we will see a rapid increase in power generated as we see increased daylight hours and better angle match with the arrays.

Next month we will be able to show the improvement in power usage for the house based on the increased core temperature mass and reduced need to back up during the winter months with electric heating.

 

July Results

Well here we are in the middle of the winter cycle and the worm has slowly turned with 135kwhrs of PV power being produced during the month which is slightly higher than in June.

The month was colder than last year with a concentrated spell of southerly winds keeping the temperature below 10 degrees for 15 days straight in the middle of the month.

There were no days where we generated more than 8 kwhrs and two below 1 kwhr for the day.

Roll on spring and summer.

June - Mid Winter is Upon Us

Well we are again in the low part of the cycle for the photovoltaic output and the core temperature.

This last month was a typical June with only 115kWhr's being produced for the month. The highest run for a day was only 7.53kWhr's on the first day of the month and nine days gave us less than 2kWhr's.

The graph below shows the comparison in monthly photovoltaic power runs for the last three years up to the end of June. Note the system started in February 2012.

The temperature in the core reserve from the DSHH system is now down to 22 degrees and this is the baseline setting for the internally heating system. This means we won't use any more heat from the core and hence we have to start back filling with electric heating, but already we are noticing through the power accounts that we are using significantly less to top up compared with the previous years. The winter sun still increases the core and keeps the floor slab within a comfortable range of 19 - 22 degrees.

Results for April and May

Its been two months since the last post, and during most of this time we have been away.
The house has continued to perform as expected and we are now just days away from the shortest day in mid winter.

The core temperature has slowly moved down to sit at 23 degrees, however the house is still keeping a comfortable 20 degrees during the day and night without any supplementary heating as yet. That may change as we get deeper into winter.

Compared with the first two years we are significantly better off and as the core continues to store more heat each year within the next 2 years we should have heating all year round.

April and May were very poor weather months with 13 days and 14 days with less than 4kwhr's being generated. Very wet and miserable. The highest day in April was 11.3kwhr's on the 1st and in May just 8.26kwhr's with the lowest just 0.554kwhr's.

April provided 167.2 kwhr's and May 150.2 kwhr's.