Did a small experiment with my kid. Using Lemon to light up a LED. Using 5c coins (copper) and Nails (zinc) as the cathode and anode. Single Lemon giving out 0.9V, insufficient to light up a LED that require 2.5V min. solution is to cut the lemon in 3, connect them up in series. 🙂
This is my setup. Over ambitions from the start.
From the start, the objective is to experiment with indoor farming with Hydroponics and growth lights, to learn as much about the technology. If successful, will do the sums and explore making it my 2nd career as a Urban Farmer.
The idea came from various articles such as this and this.
I’ve this recess underneath my bed room. Providing a good shelter from the element and space for the experiment growth.
The setup consist of 2x 150W Solar Panels charging 10x 7.2AH batteries through a MPPT solar charge controller. I’ve west sun in this location with about 3 hours of direct sunlight.
The power harvested from the sun is use to power 5m of LED growth light, water pump for irrigation and air-stone. Lights and water are controlled with timer.
The actual production area – Growth bed – is able to hold 2 x9 net-pots, with LED growth light over head. Height of growth light is adjustable. This setup is able to expand further to 4x 9 net-pots.
11 Oct 2015 – Started my 3rd crop today. This time round 1 prepared the water used for germination. Having EC 774 and pH 6.38
The EC level changes with Temperature, was about 1000 when I set it up. Changes when temp drop. 2 seeds each in the growth medium. Will monitor the progress.
17 Oct 2015 (Day6) – Sprouting.
Started 2nd attempt of hydroponics on 24 Sept 2015
24 Sept 2015 – Germinating seeds with “Diamond Water”
27/28 Sept 2015, Looks good.
30th Sep 2015 – Looks kinda leggy. Could be lack of sunlight during this period of Haze.
3 Oct 2015 – transplant over to netpot. Plant is not as big as I like, did this hoping that plant can get correct nutrient and lights.
4 Oct 2015 – This is how it look like after one day. Look at the size of 3rd leaves compare to the day before. I’ve adjusted growth light to provide lights from 07:00 to 13:00, 6 hours of lights.
Set this growth area with space for 18 netpots. Managed to get 12 reasonable sprout. Lets see how this go. I’ve got my growth light hanging where I can adjust its distance from the plant.
Getting the nutrient right is tricky, adding 50ml of A/B solution to 10 littles of “Diamond water”. I got a EC about 2.3 and pH 3.3
It’s too acidic. I’ve added “Backing Soda” to up the pH to around 6.1. Nutrient concentration wise, I added 4 more little of “Diamond water”. Solution settled down at EC of 1.965 and pH 6.55.
Learning from this, we should adjust EC before pH.
5th Oct – growing, didn’t expect the shoots to sprout out in the 2nd photo. Which one should I trim off.
6th Oct – grown a bit, not much
7th Oct – growing
17 Oct – Plant on 1st row is growing pretty well, not so for those on 2nd row. 1st row has exposure to direct sunlight. I’ve extended the growth light to 8 hours – 7am – 3pm, lets observe.
18-19 Oct – it can grow pretty fast. Look at the centre leave. This is how much it grow in one day.
40/0076 is 40 strands of .0076 cables
Spec as 1.1mm2 supporting 10A
4mm2 supports 25A
Below are data collected on the charging behaviour.
The whole exercise sparks from the observation that MPPT solar charger recording a mean 6-9W Solar output from my 2 x 150W solar panel in full sun coverage. It strike me that when the battery bank is full, we don’t pull the full power out from the panels. I want to know how much power the solar panels can push out at different time of the day, especially when I’ve only 3-4 hours of direct sunlight, is it sufficient to charge up my battery bank.
[table] Time,Panel(W),Battery(V),Load(W),Charging(A)I’ve 2 X 12V7.2Ah battery in the bank ~ 14.4Ah.
Day 1 test, Battery provided power to the LED strip after sun down for 3 hours. est 8.7Ah (2.9A for 3Hr), about 70% drain.
Day 2 charging, without load, both battery got fully charged well before 3pm. All this without direct sunlight.
The Panels should have lots of juice left to charge more batteries. Will build a bank of 10×7.2Ah battery to provide 12hours growth light for this system.
Lets compare cost effectiveness between Car Battery and SLA Battery in Solar Storage Project.
In Singapore, a new 12V45Ah Car Battery cost $100, while a new 12V7.2Ah SLA Battery cost $19.
For SLA Battery, 12V7.2Ah is the sweet spot, its most common and has best Px/Capacity ratio compare to other voltage/capacity combination.
[su_table]| Compare | Car Battery | SLA Battery |
| Type | 12V45Ah | 12V7.2Ah |
| Price | $100 | $19 |
| Save Discharge | 30% | 80% |
| Usable | 13Ah | 5.76Ah |
| Size | Big 207Lx175Wx190H 30KG | Small 150Lx65Wx93H 1.22KG |
3 x 7.2Ah SLA Battery is able to do the job of a 45Ah Car battery at smaller cost, space and weight.
SLA 12V12Ah Discharge Time VS Discharge Current
State of Charge on charging
State of Charge on dis-charging
Car Battery
Car Servicing cost.
1300 – Front Suspension
800 – Back Suspension
730 – Engine Mount
680 – Steering wheel balancing
600 – Tire replacement
8000 – Airbag
If -deregister on 1st Oct 2015 –
| Total Rebate Amount: | 01 Oct 2015 $28,121.00 | ||
| Total Rebate Amount: | 06 Aug 2019 $16,158.00 | ||
Hong Leong Finance balance loan as of 21 Aug 2015 is $33,120.
sgCarmart 2009 Nissan Presage resale price is around $70,000
Citroen take in price $52,000
| Enquire PARF/COE Rebate for Registered Vehicle | |||
| Vehicle Owner Particulars | |||
| Owner ID Type: | Singapore NRIC | ||
| Owner ID: | S6902348G | ||
| Vehicle Details | |||
| Vehicle No.: | SJS2835B | ||
| Vehicle to be Exported: | Yes | ||
| Intended De-registration Date: | 06 Aug 2019 | ||
| Vehicle Make: | NISSAN | ||
| Vehicle Model: | PRESAGE 2.5 HIGHWAY STAR 4AT | ||
| Primary Colour: | Silver | ||
| Manufacturing Year: | 2009 | ||
| Engine No.: | QR25803815A | ||
| Chassis No.: | JN1TAAU31Z0100568 | ||
| Maximum Power Output: | 120.0 kW (160 bhp) | ||
| Open Market Value: | $32,316.00 | ||
| Original Registration Date: | 07 Aug 2009 | ||
| First Registration Date: | 07 Aug 2009 | ||
| Transfer Count: | 1 | ||
| Actual ARF Paid: | $32,316.00 | ||
| Intended PARF Rebate Details | |||
| PARF Eligibility: | Yes | ||
| PARF Eligibility Expiry Date: | 06 Aug 2019 | ||
| PARF Rebate Amount: | $16,158.00 | ||
| Intended COE Rebate Details | |||
| COE Expiry Date: | 06 Aug 2019 | ||
| COE Category: | B – Car (1601cc & above) | ||
| COE Period(Years): | 10 | ||
| QP Paid: | $18,501.00 | ||
| COE Rebate Amount: | $0.00 | ||
| Total Rebate Amount: | $16,158.00 | ||
22 Aug 2015
Resale value of Nissan Presage Aug 2009 car with $126K milage – $54-57K
Citroen Grand C4 Picasso (Diesel) – $132,988
Citroen Grand C4 Picasso (Patrol) – $143,988
Mazda 5 – $124,888
Mazda Biante – $137,888
15 Aug 2015 (Day1)
23 Aug 2015 (Day8)
23 Aug 2015
29 Aug 2015 (Day9)
29 Aug 2015
12 Sep 2015 (Day28, Wk4)
12 Sep 2015
18 Setp 2015 (Day30, Wk5)
Plant get too leggy
