But now there’s the exchange rate to think about. A year ago, £1 got me around $1.40. But the pound has got weaker and the dollar stronger. Today, £1 gets me $1.20, and some analysts think the pound may drop over the next couple of weeks to $1.15.

So, why is the exchange rate important? In the long run, I foresee the pound being a stronger position than it is now. If I invested in a US stock now, and the pound appreciated 10% over the next three years, then it would wipe 10% off the value of my investment.

As a result, I’m looking at UK-listed growth stocks instead of the NASDAQ. So, here are two of my top UK growth stocks I’d buy now.

Kropz

Kropz (LSE:KRPZ) is an Africa-focused phosphate rock mining company. Rock phosphate is the raw material that’s used to produce phosphate fertilisers. The company is looking to play a major role in the food industry in the decades to come. 

The company’s main asset is in Elandsfontein, South Africa’s Western Cape province. Kropz hopes to produce rock phosphate from its Elandsfontein mine later this year. However, it has already been forced to delayed its first bulk sale, which is now forecast later this year.

Around 85% rock phosphate is used in fertiliser production. And it might not be a bad time to be entering the market as fertiliser prices have gone sky-high on the back of higher fuel prices.

Kropz also says that the Hinda rock phosphate asset in Republic of Congo could be “one of the world’s largest undeveloped sedimentary-hosted phosphate reserves“.

I’m a little concerned about when first production will be. And it’s worth noting that there’s a sizeable spread between the buying and selling price. Nevertheless, I see this stock as a good long-term investment.

Ceres Power

Ceres Power (LSE:CWR) is a fuel cell and electrochemical technology developer. There is clearly a lot of potential for any player in this area.

The company has been moving fairly slowly, but there are signs this stock might be about to take off. The AIM-traded firm recently announced that the completion of a China-focused joint venture with Bosch and Weichai Power was now expected to take place in the second half of the year.

Fuel cells won’t only be used in cars, but everything from powering homes to supporting massive cloud data centres. In partnership with Weichai, Ceres has developed a unique electric vehicle (EV) range extender system, using its SteelCell product, delivering high levels of efficiency and with very low emissions.

In June, Ceres Power also announced the signing of an agreement with Shell to deliver a megawatt-scale solid oxide electrolyser demonstrator in 2023. It will be used at Shell’s research and development technology centre in Bangalore where the hydrogen will be used in industrial processes on site. Such products could have huge potential in remote facilities or construction sites, such as Saudi’s NEOM project.

Today I’m looking at two penny stocks that I think have considerable potential, owing primarily to the changed resource environment that we’re living in.

Amid greater competition for resources, I believe that we’re entering a period of scarcity characterised by higher commodity prices. As such, I think these two innovative mining companies could be good long-term additions to my portfolio. And I think the current prices could be solid entry points.

Premier African Minerals

Premier African Minerals (LSE:PREM) shares soared in January, but the early-stage exploration company isn’t currently producing.

That not to say it hasn’t produced before. A few years ago it had active tungsten mines, but they’re no longer active.

However, the period of inactivity is soon to be over. Earlier this year, the firm moved forward with its Zulu project, located 80km from Bulawayo in Zimbabwe. Premier African Minerals has confirmed the presence of lithium at relatively shallow depth of 68 metres.

And in June, the company said it had entered a marketing and prepayment agreement with Suzhou TA&A, which would allow it to commence construction activities at the site immediately.

Premier African Minerals now expects to see first shipment before March 31, and says it will steadily build up production to around 48,000 tons of spodumene concentrate per annum.

Prices for this concentrate have been going from strength to strength since the pandemic — Spodumene is a pyroxene mineral consisting of lithium aluminium inosilicate. Lithium is increasingly demanded for products like electric car batteries.

However, it’s worth noting that mining is a cyclical industry. Commodity prices could well fall this year if we see a global economic downturn.

At 31p, I’d buy this stock for my portfolio. Although it’s worth noting the sizeable spread between the buying and selling price.

Kropz

Kropz (LSE:KRPZ) is another Africa-focused mining company that isn’t producing yet. The company mines for rock phosphate — the raw material used in phosphate fertilisers. It may play an important role in the food industry in future decades.

With fertiliser prices going sky-high, it looks like a good business to be in right now. But there’s more behind the business model. Kropz recognised that population growth in Sub-Saharan Africa was contributing to rising food demand, while fertiliser use in farming remains low on the continent.

Around 85% of rock phosphate is used in fertiliser production.

In 2010, Kropz took control of the Elandsfontein phosphate project, in South Africa’s Western Cape province.

Shares in the innovative mining company tanked in April after the group said it would push back its first bulk sale. But it hopes to make its first such sale this year.

Kropz also owns the Hinda rock phosphate asset in Republic of Congo. The asset could be “one of the world’s largest undeveloped sedimentary-hosted phosphate reserves,” the group said in a statement.

Getting production going will ease investor sentiment here. Some investors may have been concerned about the volatility of Congo and its impact on assets there.

I’d buy this stock now before production comes on-line. Once again, the sizeable spread is a concern, but I’m in this for the long run.

Some giants of the stock market do trade in pennies. Just look at Rolls-Royce and Lloyds. However these firms are not typically considered penny stocks, given their market caps, even though you can buy them for pennies.

Owing to their small market caps, true penny stocks are often more volatile than other companies on the stock market. They are also thinly traded and normally have considerable spreads between the buying and selling prices.

Penny stocks can be a good place to look for young firms with high growth potential. So today, I’m looking at two penny stocks that I’d buy today and hold for a decade.

Inland Homes

Inland Homes (LSE:INL), as the name suggests, is a UK housebuilder. Its share price has been on a downward trend over the past year, despite a very strong housing market.

In fact, it’s down nearly 50% over the past 12 months. However, it’s also down a whopping 23% over the past five days. There are several reasons for this.

The company is heavily indebted and reported another loss in late June. It posted a pre-tax loss of £8.2m for the six months ending 31 March last Thursday, against a loss of £5.8m a year ago. 

However, there were some positive signs. Revenue rose and net debt fell to £96.2m versus £132.9m at the same point last year. Net assets also grew, standing at £174m.

On Monday the company also announced a £21m land sale to a build-to-rent developer. Inland Homes is working to bring its debt to more manageable levels.

Despite the near-term challenges posed by rising interest rates and the cost-of-living crisis, I’m particularly positive on the long-term prospects of the housing industry. As such, I’d buy this stock on its long-term prospects.

Kropz

Kropz (LSE:KRPZ) is an Africa-focused mining company that may play an important role in the food industry in the decades to come.

Kropz took control of the Elandsfontein phosphate project, in South Africa’s Western Cape province, back in 2010. The company created its business model having noted that while there was rising food demand around the world, fertiliser usage remained low in Sub-Saharan Africa.

The firm mines for rock phosphate — the raw material that’s used to produce phosphate fertilisers — in Africa. And this definitely looks like a good business to be in right now as fertiliser prices go sky-high. In fact, 85% rock phosphate is used in fertiliser production.

Kropz hopes to produce rock phosphate from its Elandsfontein mine later this year. However, it has already been forced to push back its first bulk sale.

The AIM-listed miner also owns the Hinda rock phosphate asset in Republic of Congo. The asset could be “one of the world’s largest undeveloped sedimentary-hosted phosphate reserves,” according to the group.

Getting production going is perhaps the biggest issue for this company. First production will likely ease investors’ nerves.

At today’s price, I’d buy Kropz stock and hold it for the long run.

Mining company

As a quick introduction, Kropz is an African-based mining business listed on the FTSE AIM. It has assets with the aim of locating, mining, processing, and selling rock phosphate. Rock phosphate is a key ingredient in fertilisers. These fertilisers are crucial in the food production process.

So what’s the current state of play with Kropz shares? It is worth remembering that a penny stock is classified as one trading for less than £1. As I write, the shares are trading for just 8p. At this time last year, the shares were trading for 5p, which is a 60% rise over a 12-month period.

Kropz shares did reach 12p in April but fell back after a trading update that pointed towards supply issues and an impact on production levels (more on that later).

To buy or not to buy?

So what are the pros and cons of buying the shares?

FOR: Kropz could benefit from the rising demand for food linked to the increasing population throughout the world. Soaring fertiliser demand could be great news for Kropz and businesses in the industry. If mines can produce quality rock phosphate, it can sell these across the world to help boost food production. This could lead to healthy returns in the long term.

AGAINST: Like all mining businesses, issues at mines and production problems could affect performance and returns. In fact, in April, Kropz stated that a production issue at its primary mine would push back its first sale of rock phosphate later into the year. I believe this had an impact on its share price.

FOR: At current levels, Kropz shares look dirt-cheap to me. This is crucial to me as a savvy investor — I need to think about my risk-to-reward appetite. The shares are currently on a price-to-earnings ratio of just six, which looks to me like decent value for money.

AGAINST: Kropz hasn’t actually yet produced or sold any rock phosphate. This is an obvious worry for me as a potential investor. In addition to this, there are many other firms in the same industry vying for market dominance. As a small penny stock, it doesn’t have a robust balance sheet to deal with setbacks or issues that competitors could deal with much more effectively.

A penny stock I’d buy

Reviewing the pros and cons, I have decided to buy Kropz shares for my holdings. For the price I would pay, the shares don’t look too risky to me.

I would happily add a small number of Kropz shares to my portfolio and hold them for the long term, which is part of my investment strategy anyway. The burgeoning market and the vital part rock phosphate plays in food production also helped me make my decision.

Kropz

What it does: Searches for and produces rock phosphate in Africa.
Price: 8.5p per share

Producing enough food to go round is becoming increasingly hard as population levels rise and global warming worsens. It’s why companies like Kropz (LSE: KRPZ) will play a critical role in the food industry in the decades to come.

This penny stock mines for rock phosphate in Africa, the basic material that’s then used to produce phosphate fertilisers. Virtually all of these types of fertiliser are based on rock phosphate, a raw material that Kropz hopes to produce from its Elandsfontein open pit project in South Africa later in 2022.

Kropz also 100% owns the Hinda rock phosphate asset in Republic of Congo. The business has said that the project could be “one of the world’s largest undeveloped sedimentary-hosted phosphate reserves.”

Production problems

Operational news from the firm hasn’t been hugely encouraging recently. In April it warned of production issues at Elandsfontein that would push its first bulk sale of rock phosphate further back into Q2.

This delay also means Kropz has had to raise ZAR58m, it said. It’s done raise this by drawing down remaining funds from a conditional convertible equity facility and by sealing a bridge loan facility.

A big market

Buying mining shares can always be considered risky. Problems at the exploration, mine development and production stages can be commonplace. And as Kropz has shown, this can be particularly problematic for smaller operators with no revenues and fragile balance sheets.

Still, it’s my opinion that this is an attractive penny stock for me to buy. First off, its projects in Africa are potentially world-class assets. And secondly the business could profit considerably from soaring fertiliser demand.

Analysts at Grand View Research think the phosphate fertiliser market will grow from $63.81bn today to a whopping $176.06bn by 2040.

Corero Network Security

What it does: Provides products that protect websites from cyber attacks.
Price: 12.25p per share

The Covid-19 crisis had led to a sea change in employee expectations. In particular demand for more flexibility in regard to working arrangements has taken off. This bodes well for many businesses that supply software and IT services like Corero Network Security (LSE: CNS).

This particular tech stock provides protection against so-called Distributed Denial-of-Service (or DDoS) attacks. These malicious actions work by attacking a website with large amounts of fake traffic to cause a crash.

With more and more people working from home the opportunity for cyber criminals to wreak havoc is growing. Companies are therefore are having to spend huge amounts on tech security to plug their vulnerabilities. Corero itself saw revenues rocket 24% year-on-year in 2021.

A small player

The problem for Corero Network Security is that it’s tiny compared with the industry’s big beasts. Today the penny stock has a market cap a shade above £60m.

Compare this with the multi-billion (and even trillion) dollar valuations that businesses like Microsoft, NortonLifeLock and McAfee command. Corero then has a fraction of the budgets that its US heavyweight rivals have to develop and market their products.

Making great progress

Corero will have to paddle extremely hard to avoid being swept away by the competition. But having said that, I find the rate at which the UK underdog is winning business highly encouraging. And it could continue to impress as the global cybersecurity market rapidly grows.

Researchers at Quince Market Insights think this sector will expand at a compound annual growth rate of 12.5% between now and 2028. They say the cybersecurity industry will be worth a gigantic $418.3bn by then.

US Solar Fund

What it does: Invests in solar farms in the US.
Price: 88 US cents share

Investing in renewable energy stocks is also appealing to me today. I’ve taken the splash in recent weeks by buying shares in solar and wind farm owner The Renewables Infrastructure Group. I’m considering increasing my exposure by snapping up stock in US Solar Fund (LSE: USF) as well.

As the name suggests, US Solar Fund is focused on creating green energy from photovoltaic cells in the States. Its assets can be found predominantly in North Carolina with the remainder in Oregon, California, and Utah.

Favourable locations

The problem with renewable energy is that it’s sometimes more difficult to generate than electricity from fossil fuels. In the case of US Solar Fund, power generation can tumble during cloudy periods. This can have a significant impact on near-term profits and, by extension, shareholder returns.

The good news for US Solar Fund, though is that the four states it operates in receive more sunshine than the national average. The places in which its assets are located are also well distanced from one another. A wide geographic footprint helps mitigate the impact of poor weather in one or two places at group level.

I also like US Solar Fund because of the favourable legislative conditions in the US that makes it easier to operate. In fact President Biden this week announced plans to halve the amount it charges companies to build wind and solar projects on federal land in a bid to boost investment.

A top dip buy

Demand for renewable energy is soaring as public awareness over the climate change issue grows. The West’s need for clean electricity is set to increase further it tries to wean itself off Russian oil in particular.

The US Solar Fund share price has reversed sharply over the past year. And as someone who invests for the long term, this has attracted my attention. It’s my opinion that this penny stock could deliver excellent returns over the next decade and potentially beyond.

Agronomics

The rate at which the lab-grown meat market is growing demands serious attention. According to Allied Market Research, the industry will be worth around $2.8bn by 2030. That’s a whopping lift from the $1.6m that it’s currently estimated to be worth. As a consequence I’m considering adding cultured meat specialist Agronomics (LSE: ANIC) to my shares portfolio. 

Agronomics is an investment company that provides the seed money for small companies to develop lab-grown products. Competition in the industry is likely to be cutthroat as people cut animals from their diets on ethical and environmental grounds and the market grows rapidly. But Agronomics has invested in more than a dozen companies to bolster its chances of success.

Some of the companies Agronomics has in its portfolio include cultivated fish maker BlueNalu, lab-grown beef specialist Mosa Meat and egg protein manufacturer Onego Bio. As the public becomes more attuned to animal-free diets, I think profits at this penny stock could soar.

Foresight Sustainable Forestry Company

I already have exposure to the building materials industry through my investment in brickmaker Ibstock. And I’m thinking of bulking up my position in this area by snapping up penny stock Foresight Sustainable Forestry Company (LSE: FSF).

Not only is this UK share also set to benefit from rising homebuilding rates over the next decade. It’s also set to exploit the growing use of timber frames in house construction. Rising concerns over sustainability are boosting demand for wood products over alternatives. Using timber also has other practical benefits for developers like reducing build times and cutting costs.

Foresight Sustainable Forestry Company owns 27 sites in total across Scotland, Wales, and England as of today. I think it will have an important part to play in the government’s quest to hit both its housebuilding and its net zero targets. I’d buy the business even though demand for its products could sink during future economic downturns.

Kropz

You might not have heard of Kropz (LSE: KRPZ) before. However, as a miner and processor of rock phosphate it will likely have a vital role to play in feeding a growing global population. The material it produces in Africa play a vital role in fertiliser manufacturing.

Kropz’s flagship project of Elandsfontein in South Africa is the country’s second-biggest phosphate deposit. Mining here started in October and first ore was delivered to the site in December. A steady ramping-up of operations is now set for the coming months. Kropz has also carried out feasibility studies at its Hinda project in the Republic of Congo, an asset the business has described as “one of the world’s largest undeveloped sedimentary-hosted phosphate reserves”.

Kropz is a mining stock whose world-class assets give it plenty of investment potential, then. I’d buy the business even though problems with getting Elandsfontein production firing nicely could derail earnings forecasts.

Likewise Group

The floor coverings and matting industry in the UK is highly fragmented and operators like Likewise Group (LSE: LIKE) have a lot of rowing to do to keep up. It is in particular danger from larger operators that enjoy significant economies of scale.

However, Likewise has been building its position in the market rapidly thanks to a series of acquisitions. And the company has wasted no time in sating its appetite for growth following its IPO last summer and acquired Valley Wholesale Carpets at the turn of 2022.

I believe this penny stock could prove a lucrative stock to own as construction activity picks up following Covid-19. Likewise supplies flooring products for commercial, industrial, and residential spaces. And I’m particularly excited by the possibility of soaring sales to homebuilders as build rates of residential properties heat up.

Old Mutual

A number of shares in my portfolio give me access to fast-growing emerging markets. But I feel my exposure to Africa and its soaring populations could be lacking. The number of people living in Sub-Saharan Africa has been growing by around 2.7% a year in the past decade, for example. This is much higher than the growth rates in Asia and Latin America.

I’d aim to capitalise on this trend by investing in Old Mutual (LSE: OML). Wealth levels are also rising rapidly in Africa and as a consequence so is demand for financial services, an area in which product penetration remains extremely low. Old Mutual’s main market is South Africa but it also trades in other major continental economies like Nigeria, Kenya, and Ghana.

Now competition in these fast-growing markets is expanding rapidly. And this could take a huge bite out of Old Mutual’s profits. However, I think the company’s strong brand name and history (it’s been trading since 1845) could help limit the damage.

Atlantic Lithium

Buying mining shares usually involves a large degree of risk and in this respect Atlantic Lithium (LSE: ALL) is no exception. A host of disappointments during the exploration, development, and production stages can occur. These can hit profits hard and send a share’s price sinking. And in this case there’s a long way to go before Atlantic Lithium gets production firing at its Ewoyaa project in Ghana.

Still, it’s my opinion that the potential rewards of owning this penny stock makes it very exciting today. Lithium is a critical component in electric vehicles, so consumption of the metal is tipped to take off in the years ahead. Statista analysts, for example, think lithium demand will soar almost 280% between now and 2030.

Drilling work at Ewoyaa reveals massive mining potential and Atlantic Lithium recently hiked its resource estimates for the project to a huge 21.3m tonnes. I think the business could be a great way to capitalise on the green transport revolution.