Finding the right person for the job

[Fleety]

Hi, first post for me. I've learned a lot from lurking here the last few months.
I've learned enough to know I need to enlist a specialist refrigeration engineer.

I'm working on some active solar water distiller designs with a small team and after rounds of prototyping it's become clear that some models will need actively cooled condensers to knock the water vapour down fast enough.

The areas we need help with are:
- Design and sizing of condensers
- Spec of the 12or 24V cooling loops.

Any advice on where I'd go (online) to find a freelance engineer would be appreciated.
*Our team works remotely in 4 countries, so location isn't an issue.

Thanks for any advice in advance,
Fleety

[seanf]

https://ior.org.uk/technical-guidance

Theres a list of a few consultants based in the UK on the IOR website.

[Peter_1]

In which countries are you currently working? Seems interesting

[daveca]

Fleety,

Welcome to the world of Project Management.

I have experience related to that topic in electronic R&D and in the HVAC world, but not exactly in refrigeration, cooling or sealed systems.

Suggestions/Opinions/Experience:

1. It is vital to understand the differences between Science and Engineering.

Science understands the Laws of Physics and how they relate to real world problems.
Thats the phase your project is in at this point (?)

Engineering is taking those principles and making them solve a practical problem.

The two are quite different and they both must understand each-others fields, but need not be experts at them.

In order to hand this off to an engineer, the problem must be clearly defined and calculated. The output must be clearly known and predicted and must work as predicted.

Otherwise, the engineer is a bit of a 'boat without a rudder' and can go in circles, spending a project into bankruptcy. Engineers are good at spending lots of money.

The science end must be able to calculate the correct output, but not necessarily 'put it into hardware.'

The Engineer must be able to take that info and calculate a means that works the first time. The second thru n-th times become VERY expensive.

Guessing often leads to disaster.

Example, I once developed a motor vehicle propane fuel system that operated with vapour scavanged from a small tank using atmospheric heat. That eliminates a lot of expensive hardware, but implies a smaller, more fuel efficient vehicle.

The output was that I entirely calculated, designed, built a system, a vapour source, lines, filter, modified petrol fuel injectors and an electronic control circuit to modify the vehicles fuel injector pulses and the system worked the first time with a small adjustment of a potentiometer. Its a somewhat dangerous venture, so it must be calculated carefully. The only test I did was to prove propane vapour flow through a modified fuel injector using a water displacement measurement. The rest is just BTU/hr.

You (your team) must be able to clearly communicate the problem and goals to an engineer as a starting point.
Without that information, the project can go badly off course, not give the desired output and often leads to lots of project in-fighting and disagreements (personnell problems).

2. The basic question seems to be that incident solar energy is anticipated to cause water distillation from water vapour. That makes, ideally, pure water.

Thats a heating phase, and thats 'free heat'. However, condensation is the second stage and gravity isnt a strong force.

Heating is natural. There is no such thing as "cold" but an absence of heat from Thermodynamics.

Cooling, then is artificially amplified and usually by electricity. Cooling is done by an amplified phase change of refrigerant as you know. Thats artificially forced and the process also requires and wastes energy.

If the goal is a totally solar-driven process, beware. The basic implication is that insufficient solar energy exists to accomplish the goal, so that with artificial amplification and its losses, solar also cannot supply that energy demand, because a cooling system is less efficient. A surprisingly large solar panel installation may be needed to get a meaningful amount of water.

3. Solar is a popular idea, but largely a political football because its proponents do not understand, or do not wish to understand, that all our energy comes from solar, BUT, it is inefficient to directly use it.

Solar energy is captive in fossil fuel. That energy is condensed into a small volume. Very efficient.

Straight incident solar energy is both in small quantity (Kw/m^2) and VERY INEFFICIENT.

It can be used to make "small power" but alternate energies fail to supply - the critical point- large scale commercial power.

The US 2021 generated 4,000 TW. (IEEE)

Solar electrical sytems are extremely inefficient. I once calculated a household 3Kw system based on a 15% efficient panel. The calculated cost was $30,000 USD and efficiency was 8%. 92% wasted heat. That is no competition for mass commercial power generation at upwards of 44% efficiency.

So in remote locations, solar may not work for condensation.

4. It is a universal disaster to start a company to do basic research. Research is a money pit.

5. There are mechanical means to condense, a spinning mass could condense water droplets. A spinning mass has some mechanical efficiencies (Conservation of Energy)

In my opinion, you do not need to know how to design a cooler. But you (plural) must know how to calculate the points regarding Conservation of Energy, the inputs and outputs, BTU/hr, heat flows, etc as the boundaries of the system to then ensure the project is kept within those boundaries.

It is also necessary to be able to communicate that to financeers. They probably wont be interested in day to day details as 'money men' but those details are critical to a business plan.

[TrevH]

What Daveca said LOL